#help-0

1 messages · Page 731 of 1

woeful pulsar
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maybe try it out with various a and b

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b= 1, 2, 3, 4 for example

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and a=3.14156

jade peak
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b=1 --> 3.10

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b=2 --> 3.14

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u were right

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3 is also 3.14

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that is due to limit of display

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3

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it does just round based on decimal

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thanks...

sour kelp
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someone told me a graph that is symmetric with the x axis can not be a function. So what about f(x)=0?

vale wigeon
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that's the one exception

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unless it's the graph of the zero function, it's going to fail the vertical line test

sour kelp
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ok, thank you

alpine sable
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Hey, I have a question, what is x=log 0 , base e?

rigid smelt
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undefined

alpine sable
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why

rigid smelt
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because there is no x such that e^x = 0

alpine sable
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cant we even use*i , for a complex solution or is there not even a complex solution

rigid smelt
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again, it is undefined

alpine sable
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oh,

rigid smelt
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if there were i would have said its a complex number or something else

alpine sable
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ok

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thx

vale wigeon
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@alpine sable no, there is not even a complex solution.

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e^z can return every complex value except 0

alpine sable
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yes

rigid island
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hello

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question about logs

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why doesn't my method work

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the method on the left is the correct working, however, why doesn't my method work?

jagged imp
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who says your method doesnt work?

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its incomplete so far but its not wrong

rigid island
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i tried it

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but it doesn't work out to be the right answer

jagged imp
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uh

woeful pulsar
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why did you write log(4^x)

jagged imp
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the working on the left is diff to the q

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yeah what element said just saw that

rigid island
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i'm not sure , that's what the worked example said

woeful pulsar
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check if your paper has a printing error

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because the question is not 3^(2x+5)=4^x

rigid island
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there is a printing error

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my fault sorry i didn't think to check it

woeful pulsar
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yeah there probably is

rigid island
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the worked example has 4^x

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however the actual question does not have 4^x

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thanks

merry coral
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I created an algorithm to look at the winning and losing streaks of ETH on the 1-hour chart.

Here are what they look like plotted. X being the streak (-4 means 4 negative closes in a row, 4 means 4 positive closes in a row)

The amount of winning streaks is higher than losers because the market was in an uptrend.

So, question:

What's the most accurate parabola or distribution that shows this? (5159 inputs checked, let me know if you need numbers)

bleak hearth
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can some o1 help me do this question please

vernal igloo
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These are contradicting statements. It says that every point on the gold line is a solution to the equation
y = 1/2x + 3

and every point on the green line is a solution to y = x + 1 So, the only point that's a solution to both equations is the point of intersection
??

There's no solution here. y depends on what x is, so any point on the line works.

There's not something called a "solution" here.. unless I am not understanding something

if there were equations like
2x + 3y = 50
4x + 9y = 43
then here there is a solution

crisp grove
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do you know Cayley Hamilton theorem?@bleak hearth

bleak hearth
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no

crisp grove
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oke then computer pA+qI

bleak hearth
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ik how to multiply divde matrics

crisp grove
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and make them equal with A² elementwise

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you'll get 4 equation in terms of p and q and solve them

bleak hearth
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yea multply by itself

crisp grove
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yes

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computer the sum of pA+qI

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and compare

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@vernal igloo what seems to be your problem?

bleak hearth
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ok so for multiplying ig tot (5 4 -4 -3)

crisp grove
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ok

bleak hearth
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but i dont know how to make it pA+qI

crisp grove
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what's pA+qI?

bleak hearth
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2 matrices

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I is 1001

crisp grove
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yes

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you know A

bleak hearth
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yea we just solved it

crisp grove
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so what's pA? what's qI and what's their sum?

bleak hearth
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?

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ohh

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gimme a sec

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wait do i use A or a^2 when adding

vernal igloo
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like, "the only point that's a solution to both equations is the point of intersection" makes no sense there

crisp grove
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why isn't there a solution in SI form?

vernal igloo
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because you can pick any x, and find any y

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you're not trying to find something

bleak hearth
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umm i did what u said and got

crisp grove
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all the slope intercept form, or ther form are just the representation, the line doesn't change

bleak hearth
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(4 2 -2 0)

crisp grove
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u get the same solution in every form

merry coral
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lol what disribution is this

crisp grove
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@merry coral Normal?

bleak hearth
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ohh i can shsow it like this
(4 2)
(-2 0)

merry coral
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ooo

crisp grove
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@bleak hearth what's that?

bleak hearth
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u said to add a and I

vernal igloo
crisp grove
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no

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they didn't say that

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they said solution of L1 is gold, L2 is green

vernal igloo
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every point on the gold line is a solution for the first equation

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ye

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and l2 for green

crisp grove
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and the only point that is solution to both is the intersection

vernal igloo
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how is it a solution when you're not trying to solve something??
in slope intercept form, you can just pick any x, and find any y, and you get your answer.

alpine sable
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Can anybody tell me how he gets pi/2 here as a value that makes the function = to 0? I get the other two answers but not pi/2 UPDATE: Nevermind, he just added 2pi

crisp grove
bleak hearth
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Ryuzaki how do i represent it as linear?

crisp grove
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for ex y=x/2+3 will give u point in gold line only

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if u want to find a point that both lies on gold and green as well, you have to look for common points in green and gold, whic is, in this case the intersection

crisp grove
bleak hearth
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when doing A+i do i use A^2

vernal igloo
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calling it a "solution" is just weird unless the intent is to find one point that's both on the green and gold line

crisp grove
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for example
p(1 2; 3 4) + (1 0; 01) = (p+1 2p; 3p 4p+1)

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do similar to this with pA+qI

bleak hearth
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ahh

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ok gimme a sec

crisp grove
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@vernal igloo that is a solution if the system
y=x/2+3
y=x+1

these are called system of linear equations

vernal igloo
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yeah, I get that

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well

vernal igloo
crisp grove
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equivalent

vernal igloo
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because in here, you cant just pick any x, and find any y.

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but in the one you posted, you can just pick any x, and find any y for both of them

crisp grove
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u can, it requires a little rearrangement

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x-2y=-6 is equivalent to saying y=x/2+3

bleak hearth
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Ryuzaki i did what u said

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but what do i equate it 1

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2

crisp grove
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bleak hearth
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ahhh

crisp grove
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A²=pA+qI

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solve for p,q

bleak hearth
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ok i now have the values for q and p

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@crisp grove

crisp grove
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?

bleak hearth
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ok i got it but 1 question @crisp grove why do we quate A^2 to pA +Qi

crisp grove
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because question says write A^2 in the form pA+qI

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so we are equating them and solving for p and q

bleak hearth
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ahh ok tytytytytytytytyty ❤️

alpine sable
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Can someone tell me how he manipulates this to remove the square root on the right? I can't quite figure it out:

gray isle
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basics of combining fractions through addition or subtraction

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common denominator etc

alpine sable
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urgent question

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what would the range be of the inverse?

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would it be all real numbers or (3,infinity)

glass lichen
alpine sable
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i got a test tomorrow

glass lichen
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ok.. well range of f^(-1) is the same as domain of f...

alpine sable
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i agree

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by law

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but

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f(x) has a domain of all real numbers

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therefore the range of inverse would be domain of non-inverse

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but...

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as u can see

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no its domain

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yeah

gray isle
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misread

alpine sable
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all good

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so @glass lichen , ur saying this has a range of all real numbers?

glass lichen
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yes

alpine sable
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how so? it says its undefined at a certain point

glass lichen
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I mean desmos also stops it randomly, so Im not trusting what desmos says

alpine sable
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ok

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thank u

vale wigeon
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dunno i'm def not the person to ask

halcyon geode
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Unless you're doing a PhD ain't no university program requiring 50/60 hours per week

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Actually, I retract my statement cuz I don't know that much about programs outside Europe

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Well, IMHO universities over here tend to try to get some resemblance of balanced workload, they tend to fail but not so miserably as to reach 60 hours. I did had a semester where I had 38hours of lectures+exercices, but for the most part it also meant we didn't had to put more than 2-4 hours in the weekend as exercices were done in those sessions

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So up to 50,in particular semesters, I could see. But between universities trying to get a more or less standard level (with the whole credit system) and less of a workaholic culture I don't see going at that rate constantly

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Unless you're going for 20/20, which is less of a thing over here so your mileage may vary

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(to be fair, the only people getting 17+/20 on my program where people that kinda did work on their free time for fun, so maybe that's where the 50/60 hours comes from)

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Which country is it?

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Yeah no totally

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Credits between different programs are not the same

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I agree with that same here. But they give some amount of bounding. If the university goes too overboard, students will complain that it's requires significantly more time than whatever amount of credits is supposed to be worth it

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Programs do vary, but in my experience is less "this program requires 60 hours of work" and rather "this program will have an 80% fail rate in the first year and then people will have to work 40 hours per week"

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mmmh let's put it like this. Over here the med program is one of the hardest on the amount of workload, but each class is actually fairly easy (got friends there). Is just that they cover so much material that they do have 40/50 hours of workload

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meanwhile there are certain first year courses on physics and math that are known to be grinders with incredible high fail rates

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The thing is, the amount of material is not much, and grinding it wouldn't improve that much the results

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rather, students just need to get more and more exposure thorugh long process to really get the material

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because the exams require working and making proves about things tou haven't seen in class

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Dunno if i make sense?

wanton vortex
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me, someone who is interested in studying physics/math in college and is reading this: stare

halcyon geode
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Mind you, i could be totally off mark

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(Like, psychology has the same credits, but they probably put like 20 hours each week...)

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I wouldn't say the harders, but one of the hardest yeah. They fight all the time with engineering and math/physics about who has it hardest xD

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Belgium

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The thing is, i do think that med, while being really hard, is also less prone to drop out exactly because most people can grind 40/50 hours for memory if they're motivated enough, which med students tend to be

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So i don't think drop rates are the best indicators, in that case first year physics/math would take the crown with 80% drop rates

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But....it's also because for a lot of students it will be the first real math physics exposure

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When they realize physics is not nice simplifications and woah dude, and that math is not "i enjoy doing a bunch of calculations"

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That's the thing, that's subjective

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For example, i do think med students put more hours than math and engineering

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like, probably for certain

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But i don't think math students will win much by studying more, things require time to be really processed

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So any more hours than that it will be a waste

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Would be, if you could qualify that, and add "correct expectations" "same faculty culture"

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Another thing that makes med super hard here is that second year has a limited number of places

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so it doesn't matter if you pass, if you don't pass up to a certain spot in your class, you're fucked

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which is a load of bullshit, but you know, happens

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Which means math student here tend to help each other, med students tend to fucking compete against each other

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Also that

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Here a lot of people that failed the entrance exam for polytech go into physics and math thinking they'll tend simply transfer

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and get thoroughly fucked xD

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I have no idea where to get them sorry, it's also university based, so half of them will be in french, half in dutch, dunno if there are english versions

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40 yeah, but there is a lot of difference betwen 40-45 to 50-55. because it mostly means you still get a semblance of personal life. 44 hours is 8h/day on weekday +2 hours saturday/sunday. Hard, lots of work, still allows you to have a life

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after that, each freaking hour on top of that is a total pain

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But yeah, i had 38h of lectures+excercies in my first semester and the third one

lofty gorge
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To chip in I've had 40 ish hours of work a week in the UK.

halcyon geode
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studying so hard that you dilate spacetime

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Math physics minor

lofty gorge
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Average

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Maths

halcyon geode
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But yeah, bottom line, 40 hours is definitely within the average of total work, some semester you might push 45, 50/60 is another level

woeful pulsar
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looks at my expected weekly workload
70

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i overloaded math by 40%

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probably that i study at 140% speed

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because courses at this level are easy

halcyon geode
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Do you have the program?

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like, what goes inside/exams or stuff like that?

noble sinew
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50h expected work each week is pretty standard in Europe iirc

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upper limit for yourself or expected on a course?

halcyon geode
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yeah, still you're not getting multivariate calculus if the curriculum says "single variable calculus" :p

noble sinew
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undergrad

halcyon geode
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same thing over here, i'm assuming the program is rigorous :p

alpine sable
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i studied 3 h a day and got all high grades on math/physics/algebra but its my first year so it could be cus its easier material. it rly depends on the person (and yes its college

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i think as u said w lectures n stuff its not like you /have/ to dedicate sm hours to study? cus you are also learnin those hours of classes

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i did online school so i didnt rly have lectures

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videos or stuff i watched were included on those hours

heavy spear
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that is why ii am trying to finish ap calc ab and calc bc

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in highschoo,

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also take stats in 12th

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in 10th rn

alpine sable
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i think rather about time is u rly have to be jn the mindset to focus during that time

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3h isnt a lot so i was able to turbo focus and get it all in

halcyon geode
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states or europe?

heavy spear
halcyon geode
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I meant starberry, i knew you were in the states since the ap thing is from there xD

alpine sable
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oh im from argentina HAHA

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studying at university of buenos aires uba

halcyon geode
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programa de mates?

alpine sable
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not precisely, but ppl who study math do the same programme yea

noble sinew
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how tf do you not use more than 3h lol - I have 12h lectures each week+3 assignments each week + self study + excercises

halcyon geode
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Is a bit different tho, here there is the 3+2 system, argentine is the 5 year program no?

alpine sable
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yes! 6 years

halcyon geode
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In south america we tend to have a year to put people up to speed cuz our schools suck ass

noble sinew
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ah lol

halcyon geode
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I don't know about argentina in particular

alpine sable
halcyon geode
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But that's my experience back home and friends from colombia

alpine sable
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cus i took online classes

heavy spear
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lol

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honestly i can blame online classes for ruining my life xd

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cause i dont understand anything i learned so im strugling this year

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but lifes life

alpine sable
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online classes jus means u gotta self study

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sadly:(

noble sinew
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Atleast you don’t have my prof - he was new at the course and decided he wanted to make the exam totally different and harder. Result? 50% of class failed the exam (around 80 ppl).

heavy spear
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wait a min if u take calc in highschool and pass you dont need to in college from my understanding that iis the main reason im taking calc xd

halcyon geode
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Definitely not true

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You neeed a strong background of algebra, if you are confortable with the practical aspects of limits and derivatives is a big plus too

alpine sable
halcyon geode
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True, sorry

heavy spear
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true xd

alpine sable
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people be like: imma become a prof to shit these students!

noble sinew
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Lmao ye idk - however the Uni decided that the questions weren’t solveable in the given timeframe and offerered everyone another exam if they wanted to

alpine sable
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hell yea thats epic!

heavy spear
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wait a min does anyone have a idea what they could mean by odd or even

vale wigeon
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@heavy spear have you ever worked with the concepts of "odd function" and "even function"?

heavy spear
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no

vale wigeon
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and you haven't been introduced to them in class either?

heavy spear
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no

vale wigeon
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then you are being asked a question which you don't have the right tools for

heavy spear
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oh rip

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i guess the internet is going to help me

vale wigeon
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i mean, you're being given homework on something you haven't been taught.

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unless you were expected to learn about it yourself? in which case you should study the section(s) of your textbook which talk about odd and even functions.

heavy spear
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we dont have a text book

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it is so stupid

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like i have to use khan academy to learn concepts since the teacher is kinda lazy and it is inperson learning not even online

vale wigeon
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you should talk to your teacher and make them actually do their job i think

heavy spear
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ik im pretty sure the teacher hates me since i ask about 20 question on the hw every day

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lmao

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some times she just gives me answers

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withought explaining

vale wigeon
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yikes

heavy spear
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ye

vale wigeon
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i mean ok like

heavy spear
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well i am tryign my best so

vale wigeon
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i could either tell you the actual definition

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of odd and even functions

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but this will take some time getting used to

heavy spear
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ok

vale wigeon
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or i could tell you a shortcut trick which works for this exercise in particular but won't give you a true understanding

heavy spear
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nah i want to understand it cause ill prob need it for the test or somthing

vale wigeon
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okay

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we say that a function f is odd if f(-x) = -f(x) for all x, and we say it is even if f(-x) = +f(x) for all x

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in terms of graphs, odd functions have 180° rotational symmetry about the origin while even functions have reflection symmetry about the y-axis

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examples of even functions include: |x|, x^2, 1/(x^4 + 1), cos(x), etc.

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examples of odd functions include: x, x^7, sin(x), 1/x^3, etc.

heavy spear
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k

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i think that first part should help me get the answer to the question just plug and chug lmao

vale wigeon
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it is just plug and chug yes

heavy spear
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thx btw

vale wigeon
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a lot of students find themselves confused by it

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which is why i was initially apprehensive about giving it to you

heavy spear
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are you a teacher you said students ?

vale wigeon
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i'm not a teacher, though i do tutor one on one occasionally

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i mean students in a broad sense

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like, school students who come here

heavy spear
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nice

astral dagger
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Hello, I was trying to solve a question that defined a piecewise function f(t) and found some answers that I don't know if are correct or not. Either way, what I want to know is if there's a proof to this:

crisp grove
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proof of?

ocean sealBOT
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Ryuzaki

astral dagger
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indeed, I tried to solve another related question that the answer doesn't seem to satisfy it

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like, maybe it has to do with how the function was defined

crisp grove
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this statement is indeed true, u sure what you did was right

astral dagger
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,tex (f(x)=\begin{cases}1,~\text{if}~0\leq x< 1\0,~\text{if}~x\geq 1\\end{cases})

ocean sealBOT
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SubGui

astral dagger
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but it seems that

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(f\ast f=2-x,~\text{if}~1\leq x\leq 2)

ocean sealBOT
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SubGui

astral dagger
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if it indeed satisfy the statement, then I was just using it wrong

crisp grove
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how's f*f /=2-x?

vital sleet
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y did the Y(5) change into 10?

vale wigeon
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Y(5)?

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i don't see a Y anywhere in this picture

twin nimbus
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I believe he means V(5)

vale wigeon
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did you mean V(5)?

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@vital sleet

vital sleet
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oops

vale wigeon
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V(5) is 10, as you can calculate for yourself.

vital sleet
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yes

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wait what

vale wigeon
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V(t) = t^3 - 6t^2 + 35

vital sleet
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mhm

twin nimbus
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\begin{align*}
V(t) &= t^3 - 6 t^2 + 35 \
V(5) &= (5)^3 - 6 (5)^2 + 35 \
&= 125 - 150 + 35 = 10
\end{align*}

vale wigeon
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V(5) = 5^3 - 6 * 5^2 + 35

ocean sealBOT
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OmnipotentEntity

vital sleet
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ohhhhhhhhh

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im dumb

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ok thx

twin nimbus
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Not dumb.

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just learning

vital sleet
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lol

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ez

twin nimbus
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Is there an established inverse function for $y = x - \sin x$?

ocean sealBOT
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OmnipotentEntity

twin nimbus
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I know it's not elementary.

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But is there a special function? Something with properties I can reference somewhere?

warped phoenix
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I know how they solve A because I know the formula

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but I don't really know what anything means

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could someone ELI5? google's not being that helpful LOL, what exactly is the margin of error? For a., it's +/-34.81, what does that 34.81 mean

twin nimbus
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The 34.81 is the amount above and below you have to go to make a range where there's a 50% chance the true value falls within the range

warped phoenix
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50% chance that what value falls within that range?

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any given number? or the 1800

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or the 7950 😅

pine cipher
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someone please help 🥺

warped phoenix
pine cipher
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😭

twin nimbus
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So if you have an average loan value of $7950, and you pick someone randomly within the population, what is the probability that this person will have a loan of exactly $7950?

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Very low, surely.

warped phoenix
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ohhhhhh

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ok i follow

twin nimbus
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What is the probability that person will have a loan between $7900 and $8000? Higher.

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Margin of error gives us a way of formalizing it.

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Also, I'm not certain your values are correct for the record.

warped phoenix
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wdym

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for the z-score?? thats what was given to us in the question, idk what a z-score is but my teacher said we dont need to know cuz we'll learn it later

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but everything else you see is what my teacher wrote out and said was correct

twin nimbus
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the margin of error is the standard deviation * the z score

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I don't think you divide by sqrt(n) here.

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that should have already been done for you in calculating the standard deviation

warped phoenix
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thats what my teacher said to do :/

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so when the confidence level is 50% they want to know the probability of having a loan between, 3975 and 11925?

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since thats 50% and 150% of 7950

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that sounds wrong hahaha

twin nimbus
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No, use the stdev

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.67 * 1800 = 1200

warped phoenix
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we're told that it's 1800

twin nimbus
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It's the square root of the variance.

warped phoenix
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does that mean that most loans will be 1800 more or 1800 less than 7950

twin nimbus
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it means that, on average, the total loan amount will be different from 7950 by 1800

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in this case, "on average" is doing a lot of work.

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But that kinda gives you a feeling for the idea behind standard deviation

warped phoenix
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so on average, if i were to pick a random person of the sample, their loan might be 9750 OR 6150?

twin nimbus
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not quite.

warped phoenix
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😦

twin nimbus
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Let's say I choose a loan at random, and its amount is 8000. The difference in this case is 50.

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I choose another loan, this time the amount is 10,000. The difference is 2050.

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Then I choose yet another loan, this one is 2500. The difference is 5450.

#

I do this a whole bunch of times, then I take the average.

#

This is kind of what the standard deviation is trying to do.

#

The mathematics is different behind the scenes, though, for rather complex reasons that you'll learn about in a college statistics course.

#

so you get slightly different answers, but they're morally similar.

#

Does this help @warped phoenix ?

dapper tendon
#

yes pls u can share it!!

warped phoenix
#

soooo

#

the standard deviation of this example means that the typical difference of a loan given will vary by $1800?

#

so the individual loan someone gets wont be a difference of 1800, but the average difference of the entire sample would be $1800

twin nimbus
#

Yes. And the distribution of that difference is assumed to be normally distributed (which is why you're using a z score)

#

So there will be more people close and fewer farther away in a very specific sort of sense.

warped phoenix
#

ok so ive got the stdev down, but the margin of error of 34, what does that mean in accordance to this

#

the deviation is a difference of $1800, does a margin of error of 34 mean that

#

idek tbh what it could mean

twin nimbus
#

Again, I don't think that the MOE of 34 is correct.

warped phoenix
#

ahahahha thats what my teacher is sticking with ig 😅

#

but even if its wrong, what does it mean?

#

that the stdev of $1800 is off by like 34% or something?

#

idk thats my best guess

twin nimbus
#

It means, that, because your confidence level is 50%, there is a 50% chance that if you selected someone at random, their actual loan value would be in that range.

#

7950 +- 34

#

or 7916 - 7984

warped phoenix
#

ohhhhhhhhhhhhhhhhhhhhh

#

so there's a 50% chance that a random person's loan, when there is a difference of 34, will be within the range of the stdev?

#

(i think...? 😅 )

alpine sable
#

hi all how would i set up this integral?

warped phoenix
twin nimbus
#

Let's say you have a bin of balls. And half of them are blue and half of them are red. And you pick a ball and then put it back and shuffle it around each time. You'd get a series of random blue and red ball pulls. You might get 0001000001000111 (where 0 is blue and 1 is red). But each pull has a 1/2 chance of coming up either blue or red.

alpine sable
#

Two angles of a polygon are right angles and every other angle is 120 degrees. Find the number
of sides of the polygon.

#

can someone help

#

please

#

i have an exam tomorrow

#

pls

alpine sable
twin nimbus
#

Now we apply this logic to your MOE example. Let's say 0 represents a value within the MOE and 1 is a value outside of it.

twin nimbus
#

It's still 1 in 2.

#

instead of picking balls directly, you're picking a value and then examining it to determine if it's inside or outside of the MOE

#

So if you pick someone and their loan is 7000, it would become a 1. And 7943 would become a 0.

#

and the assertion is that this MOE gives the range such that whether you get a 1 or a 0 is 50%.

warped phoenix
#

so there is a 50% chance that we pick someone who's loan is in that range of -34/+34?

twin nimbus
#

Yes

warped phoenix
#

then what was the point of the stdev range?

twin nimbus
#

and if you make the range bigger the chance goes up

#

if you make the range smaller the chance goes down

warped phoenix
#

but regardless of the range, it will be within the diff. of 1800?

#

is that what the stdev is for here @twin nimbus

twin nimbus
#

Why do you think that?

#

It's not impossible for there to be a loan of $40000

warped phoenix
#

well then idk what the stdev is for then 😦

#

because the MOE is already the important range for us

twin nimbus
#

You can find any MOE using the stdev

warped phoenix
#

ohhhhhhhhhhh

#

wait yeah the stdev is kinda irrelevant here outside of the fact that it's used for the formula

#

🤦‍♂️

#

i see

#

ig i understand then, ty!!!!!!!!!!!!!!!!!!!!!

#

i love the hat in time pfp btw 🙂

twin nimbus
#

thx.

#

Bumping my question again. Does anyone know a special function or a combination of special functions that is the inverse function of y = x - sin x ? I'm trying to analyze cycloid behavior and I keep running into situations where I need to work around being unable to invert this.

twin nimbus
#

no.

alpine sable
#

ok

warped phoenix
#

sorry i cant help im in 10th grade lol

twin nimbus
#

Ok, I'll put a little bit more work into my question and ping.

velvet forum
#

is the inverse not just y = -x + sin(x)?

twin nimbus
#

The functional inverse

#

x = f(y) = something in y

alpine sable
#

What would be the most effective/fastest way to solve this problem?: One of two pumps takes 24 minutes longer than the second to fill a container. In 35 minutes, both pump the tank full at the same time. How many minutes does it take for the first pump to fill the container?

placid zinc
clever locust
# dapper tendon yes pls u can share it!!

So basically you want to solve the limit

$$\lim_{n\to\infty}\frac{n^{1000000000}}{2^n}=\lim_{n\to\infty} \frac{n^{10^9}}{2^n}.$$

We start by noting a few properties of this which are really easy to prove (for example the first two derivatives can be proven using induction). So if we differentiate the function on the same form as those in the numerator and denominator we have that

$$\dv[m]{x}x^m=m!,$$

$$\dv[m]{x}a^x=\ln^m(a)a^x,$$

where $m$ is a positive integer and $a$ is a positive real number. Now we also note that if $a>1$ we have that

$$\lim_{x\to\infty} \dv[m]{x}a^x=\infty,$$

and if $k$ is a positive integer strictly smaller than $m$ we also have that

$$\lim_{x\to\infty}\dv[k]{x}x^m=\infty.$$

Using what we have now established we can easily see why we can use L'Hôpital's rule $10^9$ times, as we would have $10^9$ instances of an $\frac{\infty}{\infty}$ indeterminate form. Do doing this we get

\begin{align*}
\lim_{n\to\infty} \frac{n^{10^9}}{2^n}&=\lim_{n\to\infty} \frac{(10^9)!}{\ln^{10^9}(2)2^n}\
&=\frac{(10^9)!}{\ln^{10^9}(2)}\lim_{n\to\infty}\frac{1}{2^n}\
&=0
\end{align*}

and thus the limit equals zero.

ocean sealBOT
#

Lorago

clever locust
#

It's a really stupid solution but it works lol

#

Hopefully I typed it up correctly, I was kind of in a rush

ionic jewel
#

10^9 lhopitals in one problem I'm a fan

lofty gorge
#

The usual method is done by considering the 10^9+1th term in the series expansion for 2^n

ionic jewel
#

wait how does that help?

#

series expansion for solving limits?

lofty gorge
#

2^n is greater than just that term, so you sandwich with that

ionic jewel
#

,w series expansion for 2^x

ionic jewel
#

2^x = sum_(n=0)^∞ (x^n log^n(2))/(n!)

lofty gorge
#

(with an n in the denominator whoops)

ionic jewel
#

yeah i was going to point that out but seemed obvious enough

astral dagger
# crisp grove how's f*f /=2-x?

the user that answered used the convolution defn. to show that (f\ast f = \int_0^t f(\tau)\cdot f(t-\tau),d\tau), such that (0\leq \tau<1) and also (0\leq t-\tau<1), in which (t-1\leq \tau<t), but then for the first integration, the integrand would be (1) and the for the second, would be (0). That part is the easiest to understand, but then he said when (1\leq t\leq2), the integral must be (f\ast f=\int_{t+1}^{1}1,d\tau=\tau~\biggr|_{t-1}^1=1-(t-1)=2-t), so (f\ast f=\begin{cases}1,~\text{if}~0\leq x<1\ 0,~\text{if}~x\geq 1\2-x,~\text{if}~1\leq x\leq 2\\end{cases}). These limits of integration didn't make sense to me.

ocean sealBOT
#

SubGui

astral dagger
#

that t is a dummy variable

quick fox
#

Are you alllowed to cancel 3x+2 in this expression

#

In the question it does not say that x does not equal -2/3

austere bridge
#

it depends on the context

quick fox
#

If the question was simplify

#

that ^

austere bridge
#

then yeah I would cancel them out and specifically say "assuming x does not equal -2/3"

quick fox
#

Ok cool ty

nocturne bronze
#

oka so what are 12(fiften)-25(twentifive) and tgen plus fore?

#

<@&268886789983436800> is it ok to mention=

tame falcon
#

Do you want to report something?

#

Or are you asking for help on your problem?

nocturne bronze
#

no thank

tame falcon
nocturne bronze
#

this is bothers account

#

ok thank

digital raft
#

Hey , i'm trying to understand what this is

#

its the mean square difference

#

but why would they divide by Y_n

nocturne bronze
digital raft
#

where Y_n is the actually value

#

as far as i know , the mean square difference is the sum of the difference squared of the actual value and the predicted value

#

<@&286206848099549185>

verbal gull
#

Here’s what I have so far

austere bridge
#

if $g(x)$ and $f(x)$ are inverses, then $g(f(x))=x$. We can take the derivatives of both sides to get $g'(f(x))\cdot f'(x)=1$, or $g'(f(x))=\frac{1}{f'(x)}$

ocean sealBOT
#

cgodfrey

austere bridge
#

so if you can find an $x$ such that $f(x)=26$, then the answer you want is $1/f'(x)$

ocean sealBOT
#

cgodfrey

verbal gull
#

so then 1/3x^2 is my final answer?

austere bridge
#

no, but you're on the right track

#

now you have to find the right number to plug in for x

verbal gull
#

So would x be 3 then?

austere bridge
#

yep

verbal gull
#

So my finally answer is 1/27

austere bridge
#

yes

verbal gull
#

Thank you

#

I can see where I didn’t clarify the answer now

hardy geyser
#

help idk wha tto do with the -8x

slender forge
#

U factored the top wrong

#

@hardy geyser

hardy geyser
#

how

#

-4 -4 = -8

#

right

slender forge
#

Yes

hardy geyser
#

wait

#

(x-4) (x-4)

slender forge
#

Yes good job

hardy geyser
#

oh i alreayd factored the -8 right

#

burhhhhhh

slender forge
#

Ya there is no -8x when factored

hardy geyser
#

ooops

slender forge
#

U can foil ur factorization to check it

#

U would have gotten something like -8x^(3)+…

#

Which obviously is not equal to any of the original terms

hardy geyser
#

for the top i was thinking of perfect squares too thats why

#

ty

slender forge
#

Np

#

Did u get a final answer?

hardy geyser
#

yes its k

slender forge
#

Good job

digital raft
hardy geyser
#

@digital raft r u in college

digital raft
#

@hardy geyser yes

halcyon geode
#

Uh, weird, dunno why they're dividing either. The difference divided would give you a relative error, but never heard about that being used for the squared deviation

winter salmon
#

what did i do wrong here thonk

#

oops forgot to put the mininum

#

sqrt 2/2

#

but its still wrong

obsidian cave
#

Wierd why does the range option let you pick the type of bracket?

winter salmon
obsidian cave
#

Is it supposed to open with a square bracket? and close with a regular bracket?

winter salmon
obsidian cave
winter salmon
winter salmon
obsidian cave
#

I assume its asking for the y value at the vertex

#

And you put the x value

winter salmon
#

oh i used wrong formula for it tinktonk

#

ty

obsidian cave
#

np

digital raft
#

@halcyon geode okay thanks will do

gloomy lintel
#

so like (2,5] means 2<x<=5

obsidian cave
#

Oh cool

#

So that explains why infinity had a normal bracket

gloomy lintel
#

Yep

obsidian cave
#

I watched Veritasiums newest video yesterday and though there were many interesting parts I was confused about one, the one at the 7:56 timestamp (here https://youtu.be/094y1Z2wpJg&t=476 ) (PS if you didnt watch the full video you definitely should)
He says that (using 3n+1,) on average an odd number is multiplied by 3/4 to get to the next odd number, and apparently does that by getting the geometric mean, he shows the sequence he uses so I drew the pattern from it (it can also be drawn from his
explanation)
3/2 * 1/2 + 3/4 * 1/4 + 3/8 * 1/8 ....
Essentially each term is 3/(2^(2n)) and it is summed from n=1 to infinity, evaluating it numerically as well as on Wolfram Alpha shows it equals 1. Even ignoring the geometric sequence and brute forcing the original problem as such (in python)

def next_odd(num):
    """Returns the factor multiplied by to reach the next odd with 3n+1"""
    num0 = num
    num = 3 * num + 1
    while not num % 2:
        num //= 2
    return num/num0

# get factor multiplied by for 100,000 big odd numbers
L = [next_odd(i) for i in range(100001,200001,2)]

# get average factor
print(sum(L)/len(L))

shows that on average going from one odd to the next multiplies by 1. What am I doing wrong? How did Veritasium get 3/4? Clearly he must be right because odd numbers do eventually drop to 1 with 3n+1

The Collatz Conjecture is the simplest math problem no one can solve — it is easy enough for almost anyone to understand but notoriously difficult to solve. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

Special thanks to Prof. Alex Kontorovich for in...

▶ Play video
#

Sorry for the wall

austere bridge
#

you're calculating the wrong thing. You should find next_odd(i) / i, and find the average of that

ionic jewel
#

also this the heuristic approach to the collatz conjecture, and you can read that relevent part of the Wikipedia page if you are so inclined

austere bridge
#

oh nvm I misread the code

alpine sable
#

Makes it easier to read

obsidian cave
#

How do I do that?

alpine sable
#

```

obsidian cave
#

Alright thanks

ionic jewel
#

```py
code here
```

#

py for python

topaz scaffold
#

Ohhhh

#

That's what I was missing all this time

obsidian cave
#

Ah there we go

#

Thanks bunny

austere bridge
#

@obsidian cave I think you want the geometric mean, not the arithmetic mean

#

instead of $S=\frac{a_1+a_2+\cdots+a_n}{n}$, you want $M=(a_1\cdot a_2\cdots a_n)^{\frac{1}{n}}$

ocean sealBOT
#

cgodfrey

obsidian cave
#

Ohhh

#

Wow I just assumed I knew what geometric mean meant

austere bridge
#

you might have to get clever about trying to calculate it in python, though

obsidian cave
#

Any idea why use this over arithmetic mean? I mean the statement "on average an odd number is multiplied by 3/4 to get to the next odd number" seems to more apply if an arithmetic mean was used

austere bridge
#

I'm not completely sure why

#

oh wait I just realized I wrote that wrong

#

$M=(a_1\cdot a_2\cdots a_n)^{\frac{1}{n}}$

ocean sealBOT
#

cgodfrey

austere bridge
#

oh the two are the same lol

#

but you might run into trouble naively trying to compute that in python

obsidian cave
#

I think it could work with mpfr using gmpy2

#

It has arbitrary precision floats

austere bridge
#

yeah, doing something like that would also work

obsidian cave
#

I'm trying it with 100000 bit floats and as n increases the mean just constantly decreases, down to something e-300 at n=1000

#

Increasing precision isnt helping

thorn kindle
#

Just a simple 2liner. Take an arraylist, find the product, then raise it to the power of 1/size

keen saddle
#

An arc is basically a line segment limited between 2 points of a circunference?

glass lichen
#

line segment would be the chord

austere bridge
#

@obsidian cave

def next_odd(num):
    num0 = num
    num = 3 * num + 1
    while not num % 2:
        num //= 2
    return num

L = []
for i in range(1,2001,2):
    L.append(next_odd(i) / i)

prod = 1
for i in L:
    prod *= i
prod = prod ** (1 / len(L))
print(prod)
#

the following gives a number close to 0.75 in naive python

#

but it breaks if you make the upper bound much larger

obsidian cave
#

Why next_odd(i) / i ?

austere bridge
#

I moved the division out of the next_odd function

austere bridge
#

it's the same code

obsidian cave
#

Oh my bad didnt see that

#

Alright thanks I see then

#

I wonder if theres a way to get the geometric mean from the terms 3/2 * 1/2 and 3/4 * 1/4

twin nimbus
#

You mean a weighted geometric mean?

#

Or?

shut rampart
#

a bit confused on which one i got wrong and why

twin nimbus
#

Please don't ping helpers if it hasn't been 15 minutes

shut rampart
#

didnt know the rules

#

i think it has something to do with the horseshoe lookin thing on the bottom

#

but idk

twin nimbus
#

Independence is when P(A|B) = P(A)

#

If you rewrite the intersection in terms of the conditional probability you can figure out the second. But the first is clearly dependent

shut rampart
#

oh

#

yeah

#

just realized how dumb i am lol

#

i forgot that the | line means given

shut rampart
#

i thought that 3 to 2 odds means that out of 5 possibilities it will be 3 the one way and 2 any different way

lofty gorge
#

"against"

shut rampart
#

ok

#

i am terrible with actually reading questions

#

how about this

#

@lofty gorge

#

i know that A is right

lofty gorge
#

What did you do for c

shut rampart
#

and that B is 0,08

#

but i forgot the formuila for C

shut rampart
#

and averaged it

#

i think

lofty gorge
#

winning with rain and winning without rain?

shut rampart
#

yup

lofty gorge
#

you have to multiply those terms by the chance of it raining

shut rampart
#

oh

#

so

#

um

#

wait how does that make sense @lofty gorge

#

i got 3/25 and 8/25

#

and i added them

#

but if i multiplied both by the chance or it raining it would be tiny

lofty gorge
#

I forgot to write something down

#

My bad

#

It's P(rain)*P(winning with rain)+P(not rain)*P(winning with no rain)

#

However you say that in words

shut rampart
#

ok

#

let me do that rq

lofty gorge
#

("or not, respectively" should be at the end of what I said initially)

shut rampart
#

28 percent chance of winning

lofty gorge
shut rampart
#

its 0.8x0.32 + 0.2x.12

lofty gorge
#

By winning with no rain I meant the 60% in the question

#

My bad I was ambiguous

lofty gorge
#

I would write winning and no rain if I meant the 0.12

shut rampart
#

but then shouldnt the second one be .4

#

instead of the other thing

#

.32

lofty gorge
#

b is P( losing n not rain)

lofty gorge
#

where the n is that

#

I'm asking for P(rain)P(win | rain) + P(not rain)P(win | not rain), and 0.12 is P(win n not rain)

shut rampart
#

uh

#

huyh

#

huh

#

ok

#

nvm

#

so then it is .26

#

wiat no

#

.3

#

.,4

#

.4

#

yeah it s .4

lofty gorge
#

The values given in the question are "if it rains, this is the probability of winning after that". Part b is asking for "not raining and winning", not "if it rains, what is the probability of them winning". For the formula you need in c, you need the first, not the second kind

#

Is that clearer?

onyx chasm
#

is this chat occupied?

viscid topaz
#

Open

onyx chasm
#

okay well

#

$$\text{where did I go wrong?}$$
$$\lim_{n\to\infty}dx\Sum[i=1]{n}f\left(a+i\cdot dx\right) \mathop{=}\limits^{set} \lim_{n\to\infty} \Sum[i=1]{n} f(i)$$
$$dx=1\text{, a=0} \implies b=n \because dx=\frac{b-a}{n}$$
$$\implies \lim_{n\to\infty} \Sum[i=1]{n} f(i)= \lim_{n\to\infty}\int_0^n f(x) dx$$

ocean sealBOT
#

Pedrosso

onyx chasm
#

and if you're gonna tell me it's because dx=1 and dx should approach 0, tell me why that would mess it up

astral dagger
onyx chasm
#

unless of course I'm not wrong but Im just assuming I'm wrong because I'm always wrong

onyx chasm
#

I actually haven't proved myself wrong and I'm trying to find a convergent series to try to prove it wrong. But it looks wrong

alpine sable
#

i know test are not allowed but are u guys allowed to help on a task that is both assessment + assignment or is it not allowed

alpine sable
#

ok

red lagoon
#

anybody know what property the 2nd line used to get f = l/2T_s

ionic jewel
#

i don't see that being done anywhere

#

of course I don't really understand the problem z but the 1/2T_s i think you mean was in front of the sum before

astral dagger
# red lagoon

that star means convolution or is another property?

restive glacier
#

dy/dx=(dy/du)(du/dx) can I cancel the du?

placid zinc
#

That equation is true, and we call it the chain rule

#

Be aware of "cancel the du" as these aren't fractions, but notations for derivatives

restive glacier
#

So (dy/du)(du/dx)=(dy/1)(1/dx) is false?

ocean sealBOT
#

Pedrosso

restive glacier
rigid smelt
#

that is false

placid zinc
#

dy/1 is jibberish

rigid smelt
#

that is like saying derivative of y wrt 1 where 1 is a variable

restive glacier
#

Ok thanks

echo aurora
#

hey can i get help

#

dm me soon plz if u can help

rigid smelt
#

why not just post it here?

#

and dont ask to ask

#

just ask

echo aurora
#

cause i dont wanna post the questions in here

rigid smelt
#

oh well too bad then

echo aurora
#

its like college questions

rigid smelt
#

no one is judging you

#

if you cant post here then you are the oen with disadvantages

echo aurora
#

im not worried abt judging im worried abt the questions being leaked getting traced

#

like the college seeing it

rigid smelt
#

🤷‍♂️

#

that means you are cheating or something thinkies

echo aurora
#

nah im not

rigid smelt
#

sounds very suspsicious

echo aurora
#

im just tryna relearn how to do piecewise functions

#

A car company charges $35 a day to rent a car for the first 6 days. The charge then drops to $25 a day for each additional day up to 6 days. After that, the rate drops to $12 a day. The rental company does not allow you to rent a car for longer than 3 weeks. There is also a one-time rental free of $40. Define a piecewise function

#

this is an example

#

how would u turn that into a piecewise function

rigid smelt
#

so what have you tried?

echo aurora
#

i barely remember it, as far as i got was 35b and 1 </ b </ 6

#

but i fr dont remember any of it

rigid smelt
#

first of what is b supposed to represent?

neat rose
#

can someone help me

#

distributive property is hard

#

for me

rigid smelt
#

secondly, what does </ supposed to represent

#

channel is busy

echo aurora
#

days

rigid smelt
#

please move

alpine sable
#

what is 444,214,773,035,046,582,606 divided by 2?

echo aurora
#

</ is less than or equal to

rigid smelt
#

ok

#

well i mean

echo aurora
#

i have multiple questions to go thru and i dont really have time to fully learn it but if you can give me the equation for the first 6 days and then how to connect that to the next time frame i should be able to do the rest

rigid smelt
#

technically you just have to divide it into two cases

#

like how you did, in the case with 1<=b<=6

#

tho im having a bit of trouble analysing the question

#

they are asking to draw a piecewise function for the rent?

#

and what is the condition for the one-time rental fee?

#

how long is that one-time rental?

#

and also, how long of a period do they want us to draw the piecewise function over? 3 weeks?

echo aurora
#

thats all it gives me, im not sure

#

maybe we can move to a different question?

rigid smelt
#

why?

#

i mean if you want to

#

but the question does seem to be a bit ambiguous

echo aurora
#

thats why i wanted to skip it till maybe we do other questions and maybe we might learn what its asking for from doing other stuff first

rigid smelt
#

since we are goign to be graphing money against time but they didnt tell us how long of a period we should graph it

#

sure

echo aurora
#

ok so im given a parent function, given a transformed function

#

it says to write the transformed function in terms of the parent function but i thought thats already done when u make a transformed function>

rigid smelt
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yeah it is

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weird

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or did they just tell you the transformation?

echo aurora
rigid smelt
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ah ok

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so basically, they want you to write it in terms of f(x)

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and not in terms of x

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for example, a transformation h(x)= x^2 + 2 where the parent function is f(x)=x^2 can be written as h(x) = f(x) + 2

echo aurora
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oh ok

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let me see if i can do it and u can tell me if im right

rigid smelt
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sure

digital radish
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Hey guys can I have some help

echo aurora
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g(x)=3f(x-2)+4?

digital radish
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Uh

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I have a question

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Can I ask here?

rigid smelt
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its currently occupied

digital radish
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Fuck

rigid smelt
digital radish
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I'm new here

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Can questions be asked in general

rigid smelt
echo aurora
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how about that one

rigid smelt
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what are you tasked to do here? write the transformation in terms of x?

echo aurora
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same thing as before just different ones to fill out

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gives u different info

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that second box is the parent function, 4th box is the way it changes

rigid smelt
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yeah just write out what h(x) would be

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what do you think h(x)=?

echo aurora
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g(x)=.75(x+1)^2-2?

rigid smelt
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not 0.75

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oh wait

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nvm, sorry miscalculated

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but the constant is not -2

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remember, f(x) = 3x^2 -5

echo aurora
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so +3?

rigid smelt
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no

echo aurora
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or -7

rigid smelt
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f(x+1) is multiplied by 0.25

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dont forget that operation

echo aurora
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20

rigid smelt
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no...

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5 * 0.25 -2 is not 20

echo aurora
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18

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i was just doing the dividing first

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to make sure i was doing the right thing

rigid smelt
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no 18 is not correct

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0.75 * (x+1)^2 is correct

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now its just the constant that you are wrong

echo aurora
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5 x .25

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is 20 right

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minus 2 is 18

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what am i missing

rigid smelt
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no

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you do know that 5 * 4 is already 20 right...

echo aurora
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Where’s the 4 coming from

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Bro ur making me feel stupid just help me out 🤣

rigid smelt
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no im just giving you an example of why 5 * 0.25 is not 20

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this is just simple multiplication....

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ok instead of writing 0.25, i will write 1/4

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can you do 5 * 1/4 - 2 now?

echo aurora
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Wait I swear u said 5/.25

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So -.75

rigid smelt
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not that either....

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idk you but theres no way to read * into /

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oh didnt see you wrote -0.75

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yeah its -0.75

echo aurora
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Ok one sec

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ok so i did the rest of the other questions for that

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so now i have a composite function

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and i have to turn it into f(m) and m=g(x)

rigid smelt
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right

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do you have a specific problem?

dull oak
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someone help pls

fringe robin
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9=10-1 99=100-1 and so on

dull oak
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?

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how does that help

fringe robin
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use that to add

placid zinc
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Add 1 to every term, ez sum

dull oak
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oh i see

placid zinc
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Then subtract after

ionic jewel
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eg 9+99 = 110-1-1

fringe robin
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ye

ionic jewel
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yes

placid zinc
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But that's a large number isn't it

dull oak
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so would it be

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11111111...(2020 times) - 2020?

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so it would be 2016 ones?

ionic jewel
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not quite

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notice 9+99 isn't 11 (2 times) - 2

dull oak
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wait

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so how would i do it

ionic jewel
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1111(2020 times) then a 0 - 2020

dull oak
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wouldnt that lead to 2016 1's?

ionic jewel
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kinda thinking it was 2017 or 2018

ivory crypt
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you should consider how many 1 in 11110-2020, then add 2016,I think answer is 2016

inland horizon
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i think it's 2016 ones too but never saw a problem like that so i'm no t sure

ionic jewel
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,calc 11110-2020

ocean sealBOT
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Result:

9090
ionic jewel
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don't mind me, i can't do mental math

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2016 looks good then

dull oak
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yeee

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ty

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very helpful perspective

steel horizon
cerulean vine
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Yo

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Can anyone help me

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If possivle

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Possible

steel horizon
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dont ask, just put the question 😉

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its a helping server matey

night geyser
cerulean vine
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Here they are

steel horizon
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wait

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these are not english

cerulean vine
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It is?

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Looks like its not dual lang

steel horizon
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OOH

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YEAH I SEE

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I SEE

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sorryy

inland horizon
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Posting in different channels is not allowed kingarthur

cerulean vine
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I found these online

steel horizon
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btw im not a genius so i cant help 😦

cerulean vine
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Ohh

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Its on gradient of a straight line

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If thar helps?

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@inland horizon what do you mean

inland horizon
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the rules of the server to ask for help stare

crisp grove
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slope = rise/run

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u can count the run and rise so

cerulean vine
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I asking for solution and explanation

plush wagon
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What is Derivative of sin^2y = 0?

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Is it " cosy.2siny y' " or just "2siny y' "

ionic jewel
plush wagon
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dy/dx

ionic jewel
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2sin(y)cos(y)y' then, yes

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chain rule important

plush wagon
ionic jewel
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here's a Wolfram for your problems

plush wagon
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But answer doesn't include cosy

ionic jewel
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,w derivative of sin^2(y(x)) wrt x

plush wagon
ionic jewel
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yep, answer is correct

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it probably gets cancelled with the other term or something?

plush wagon
carmine lion
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wait is this channel occupied

ionic jewel
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,w derivative of sin^2(y(x))+cos(xy(x)) = k

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what is that k thing?

plush wagon
ionic jewel
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fine Wolfram if you don't want to be useful

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well anyways let's do the second part

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derivative of cos(xy)

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-sin(xy)(y+xy')

plush wagon
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Yes that's what I got

ionic jewel
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2sin(y)cos(y)y'-sin(xy)(y+xy')= 0

plush wagon
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Yes

ionic jewel
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y'2sin(y)cos(y)-ysin(xy)-y'xsin(xy) = 0

y'(2sin(y)cos(y)-xsin(xy))= ysin(xy)

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cos doesn't go away as far as I can tell

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unless there's some magical trig identities

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expand our sin(xy) and it magically cancells?

cerulean vine
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Imma learm herons formula because of this discord

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I needa understand derivatives

ionic jewel
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,w y'2sin(y)cos(y)-ysin(xy)-y'xsin(xy) = 0

cerulean vine
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Am i to young to to be learning derivatives

carmine lion
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age don't matter

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all that matters is that u can understand the concept

ionic jewel
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also i don't think herons formula has derivatives

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isn't it something with geometry

cerulean vine
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Ohh wait im dumb

ionic jewel
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and yeah idk @plush wagon either book is wrong or there's some weird trig tricks i don't want to work out

carmine lion
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@ionic jewel can u help with my question pls

cerulean vine
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Sin cos and tan come under geometric transfo?

ionic jewel
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sin cos and tan are trigonometry

plush wagon
carmine lion
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those are trig funtions arthur

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sine cosine and tangent

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how can i do part (c), i've done (a) and (b)

ionic jewel
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oh

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hmm let's see

carmine lion
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if i solve for the intersection i get this

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,tex x^3-(m+1)x+(3-2m)=0

ocean sealBOT
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abe
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

ionic jewel
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first of all the derivative is 3x^2 -1

cerulean vine
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This discord server makes me feel dumb

ionic jewel
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we want the slope of the line at a point such that it goes through point P

cerulean vine
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Im 14 and in the uk you finish school at 17

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So we gonna learn this stuff like next year

ionic jewel
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so assuming we are finding the x value where this is true, we need the line to satisfy,

slope is 3x^2-1, goes through (x,y), and goes through (-2,-3)

ionic jewel
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so what's the general form of a line that goes through (x,y) and (-2,-3)?

ocean sealBOT
carmine lion
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thats 1 right?

ionic jewel
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what?

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why is it an a?

carmine lion
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if a is the x-coordinate

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of the intersection