help-0

[lapis valley]

👍

[naive cradle]

can someone help me with this ? https://cdn.discordapp.com/attachments/744253218128658442/894798037958950932/unknown.png

[wary jungle]

can someone help me understand?

[cyan terrace]

What’s f(1) for both functions?

[pliant jay]

discontinous at x=1

[light sleet]

my teacher didnt teach me this formula correctly

can someone teach it to me?

[lilac nest]

Your teacher did teach you the formula correctly, it's just that now you're given the diameter instead of the radius

What is the relationship between the diameter and the radius of a circle?

[light sleet]

Hmm, well I dont understand it is what im saying

[lilac nest]

Do you know this?

[light sleet]

vaguely, the diameter is usually the number inside the circle with the line

right?

[lilac nest]

I meant what's the diameter compared to the radius, which is what you need to calculate the area

In the formula r is the radius of the circle

[light sleet]

Yeah, I don't know how to calculate/do that

[rigid wind]

radius is half diameter

as seen in the geometry

draw a line across the center of the circle, you can see diameter length is length of 2 radii

[light sleet]

w u t

[lilac nest]

https://images.app.goo.gl/5JQXcobL1UboHkTA8

[lilac nest]

The diameter is just 2 times the radius

[light sleet]

yeah, I was saying the diameter is the line inside the circle

so..

[lilac nest]

.

[light sleet]

6 x 2?

[lilac nest]

No

[alpine sable]

[lilac nest]

.

[light sleet]

hm i see

[lilac nest]

r=d/2

[wary stream]

$r=\frac{d}{2}$

[ocean seal]

dldh06

[wary stream]

If you wanted better format

[light sleet]

divide..?

[lilac nest]

Thx

[rigid wind]

did you learn divide

why is that surprising

[alpine sable]

[lilac nest]

Yeah if radius is half the diameter

[light sleet]

kk one sec

[wary stream]

If you don't have anything useful to comment, then stop

[light sleet]

6 divided by 2 right?

[lilac nest]

Yeah

[light sleet]

3

[alpine sable]

[lilac nest]

Now you have the radius, just plug it into the formula to find the area

[light sleet]

and how must I do that? do I just put its as A = 3 Ft^2

?

[lilac nest]

No

The formula you used before was to find the radius from the diameter (r=d/2) so now you just have the radius, which is 3

[wary stream]

The area formula is $A = \pi r^2$

[ocean seal]

dldh06

[lilac nest]

Now you have to use the formula A=r²π to find the area, whit r=3

[light sleet]

ok

[light sleet]

im starting to think you take the R, multiply or divide.. SOMETHING to get the answer

[rigid wind]

R, r both means radius here

[lilac nest]

A=r²π means A=r x r x π

[wary stream]

Also, in the problem it states to use 3.14 as pi

[lilac nest]

Yeah so r x r x 3.14

Which becomes A = 3 x 3 x 3.14 with the radius you have

[light sleet]

so 3 x 3 x 3.14... kk

28.26?

[lilac nest]

Yep

[light sleet]

Hmm I see now

ty for your help and patience with my slow ass brain

[lilac nest]

Np you're welcome

[wary stream]

What are you having trouble with?

Because do long division

[onyx kettle]

Right.. I forgot

[tawdry raven]

I’m confused where I’m going wrong with this problem

I did tan(A@)25/21 but it was incorrect

[tight locust]

maybe this will help you with understanding the naming conventions behind the sides and angles of triangles

the angle and its opposing side are the ones that share the same letter

so then you have the eq tan(25/21) = A

,w arctan(25/21) degrees

[ocean seal]

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

Requested by EndTimes#8053

[tight locust]

,w 0.8721365 radians to degrees

[ocean seal]

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

Requested by EndTimes#8053

[tardy scarab]

Hi so I need help in this question

[tawdry raven]

Yes A=a and b is adjacent right?

[tardy scarab]

I cant get the 4th one

And for 3rd it is 1/3, ¹2/3, 5/6, 4/9 right?

[tawdry raven]

Omg see I didn’t do this

[tight locust]

yeah. so the equation is tan(A) = 25/21

[tawdry raven]

I just did Tan(A)=25/21 and thought solving that equals answer

I completely forgot about arctan

[tight locust]

how else do you solve it without using arctan lmao?

you literally have to in order to isolate A on the left side

[tawdry raven]

I input it in my calculator I have no clue

[tight locust]

make sure it's in degrees

[tawdry raven]

I got 49.97

[tight locust]

yep

[tawdry raven]

Rounded to closest degree got 50

[tight locust]

good job

[tawdry raven]

It’s correct tysm

[paper canopy]

If there are ten people in a race, how many possible ways can the top five finishers be determined, assuming there are no ties?

[tawdry raven]

Would be formula a!/b!(a-b)!

[paper canopy]

30240 ?

[tawdry raven]

a=10 and b=5 and plug them in

You should get 10!/5!(10-5)!

So then, P=3628800/120*5! @paper canopy

[paper canopy]

252

[tight locust]

10!/5!^2

this is a basic mathematical fact

(2n,n) = (2n)!/(n!^2)

[paper canopy]

compare

[tight locust]

?

[tawdry raven]

Correct

[eternal pumice]

if f(x) = 1 / (2 - f(x-1)), f(0) = 0, what is f(x)?

I know f(x) = x / (x+1), I need to know the solution

[tight locust]

f(x) = 1/(2-f(x-1)), f(0) = 0
0 = 1/(2-f(-1)) => 0 = 1

impossible

?

[eternal pumice]

x >=0 I mean

[tight locust]

you just told me f(0) = 0

if f(0) = 0 then this is unsolvable

[eternal pumice]

substitute f(x) = x / (x+1), the equation is valid for this

[tight locust]

ok that makes more sense. -1 has to be a pole

[eternal pumice]

yeah, domain is x>=0

[tight locust]

so then we have |f(-1)| = infinity

let's try letting x = 1

f(1) = 1/2

[eternal pumice]

yeah

[tight locust]

this doesn't seem like enough to actually solve for f(x)

i mean the solution makes sense but you could easily multiply this function by, for instance, cos(pi*x) and get another equally valid function

are you merely to solve for any function that satisfies this or a specific and unique solution

[eternal pumice]

cos(2pi * x) you mean

but cant we say that for any function then

[tight locust]

yeah good catch there

[eternal pumice]

like if I get f(x) something, f(x) + 0*g(x) is also a solution, but actually they are same things

[tight locust]

the 0 function is the additive identity

f(x) + 0 = f(x)

[eternal pumice]

yeah and f(2pi * x) is always 1

[tight locust]

and the 1 function is the multiplicative identity
1*f(x) = f(x)

[tight locust]

only at the integers

[eternal pumice]

see, I am solving a DP problem where I come to this part, x is positive numbers only

my bad, should have told you about positive number part

[tight locust]

positive reals?

[eternal pumice]

sorry natural numbers I mean

positive integers

[tardy scarab]

Anyone know for 6th

I'm ded here

[tight locust]

ok so the domain of f(x) is Z>=0 and the codomain is Q?

[eternal pumice]

yes

[tight locust]

or Q+?

just post the actual question lmao

[eternal pumice]

yeah it will be positive only, I have this recursive equation and I have to find value for any positive integer n given in the input

f(n) I have to find

is it clear now?

[dense wadi]

There is a set of chips of 4 different colours (there are at least 8 chips of every colour). It is necessary to put 8 of these chips in a row (from left to right) in such a way that any two adjacent chips are of different colours, and at least three colours have to be used. How many ways of doing it are there?

[tight locust]

then yeah what's the issue? you've found a sequence that satisfies the recurrence equation

[eternal pumice]

Yeah but I need a formal solution for this

[jaunty crane]

number with the sum of its digits which equals to 4

pls give me example

i dont understand

[dense wadi]

13

[jaunty crane]

how

[dense wadi]

1+3=4

or 31..3+1=4

[jaunty crane]

owh

if 10 to 30

which number can include

[dense wadi]

only 13

[jaunty crane]

oh alright sir thank you

[dense wadi]

someone? <@&286206848099549185>

[alpine sable]

it's 1/8 feet right idek for sure

[inner sentinel]

is this right

[plush wagon]

I need help

how do i solve this?

[plush wagon]

is g(x) also differntiable because g
(x) = f(x)/x?

[alpine sable]

first attempt, LETS FUCKING GOOOOOOO

what does that mean?

i know $\frac{dy}{dx}$ and $\frac{d^2y}{dx^2}$ but am confused as to what having only $x^2$ at the bottom means

[ocean seal]

Bouldering

[sacred sapphire]

ive never seen that notation

[alpine sable]

ill ask my teacher

[sacred sapphire]

there are two possibilities

[alpine sable]

if you could narrow it down for me thanks

[sacred sapphire]

first possibility: its a typo

second possibility, d is just some constant and the question just wants you to evaluate the expression when that x = pi

3rd possibility, its notation i havent seen before in which case i wouldnt be able to help you

[jaunty crane]

@sacred sapphire can you please help me

[sacred sapphire]

sure

[sacred sapphire]

no guarantee that ill get it tho

[jaunty crane]

ok

theres english below the question

[harsh belfry]

For some reason I'm having a hard time understanding what has happened in this video on implicit differentiation

The original equation is:

In the video product rule is utilized on 2xy

However, I am not sure what he did once he put it into product rule.

It doesn't look like the product rule I was taught where fg'+gf'

What did he do?

It isn't explained in the video.

[slow girder]

Oh srry

[harsh belfry]

Am I just misunderstanding what happened?

What should I do?

[verbal ermine]

you need helping differentiating 2xy?

[harsh belfry]

Yes please!

What should I do?

I can see what he does, but I don't necessarily understand it.

[harsh belfry]

Is there a formula I could use?

[verbal ermine]

give me 5 mins and ill help

[harsh belfry]

👍

[sinful chasm]

you're basically using product rule here

[harsh belfry]

Any chance you would be able to explain the process?

[sinful chasm]

I could try

[harsh belfry]

Would appreciate that

[sinful chasm]

so when you differentiate y wrt to x, its dy/dx right

[harsh belfry]

wrt?

[sinful chasm]

with respect to

[verbal ermine]

with respect to

[harsh belfry]

o

[sinful chasm]

what do you get when you differentiate x with respect to x?

[harsh belfry]

dx/dx?

[sinful chasm]

yep

now lets try using the product rule

which says f'g+fg'

so take xy

[harsh belfry]

👍

[sinful chasm]

can you try it now?

[harsh belfry]

um

[sinful chasm]

okay look

[harsh belfry]

😅

[sinful chasm]

take f as x, and g as y

[harsh belfry]

okay

[sinful chasm]

we found what differentiation of x is

and what the differentiation of y is

[harsh belfry]

x(1)+y(1)?

[sinful chasm]

okay wait lemme write this for you

sorry its a bit messy lo

[harsh belfry]

reading through it

[sinful chasm]

someone else could probably do a better job explaining it, im also just doing calc 1 right now lmao

[harsh belfry]

so when given xy

you differentiated x with respect to x

y(x/x)

?

[sinful chasm]

both x and y are variables, so you cant take one out as a constant

[harsh belfry]

has to be both

right

[sinful chasm]

you understand the product rule right

[harsh belfry]

I do

or at least i thought I did before this

so f would be x f' would be.... x/x?

[sinful chasm]

no dw

whats f

oh right

f' means differentiating f

[harsh belfry]

differentiating it from y

right

[sinful chasm]

one sec

okay instead of y, if we use y=(x+3)

how would you do the product rule

x(x+3)

[harsh belfry]

oh lord Im just blanking

second

[ocean seal]

tranfi

[sinful chasm]

there

[harsh belfry]

just making sure

f here is x+3

and the derivative of it

is x(x+3)?

[alpine sable]

someone

anyone

[harsh belfry]

It just looks so unusual

[alpine sable]

only c btw

[harsh belfry]

I'm so used to seeing things like 3x^2 and such

I haven't touched expressions like these

I feel so damned stupid

[sinful chasm]

$x'\left(x+3\right)+x\left(x+3\right)'$

wait oops

$x'\left(x+3\right)+x\left(x+3\right)'$

[ocean seal]

tranfi

[sinful chasm]

Does this make sense

[harsh belfry]

the prime of x and the prime of (x+3)?

[sinful chasm]

prime basically means differentiate

in this case

[harsh belfry]

oh man Im so lost

[sinful chasm]

thats the product rule right: f'g+fg'

[harsh belfry]

ok yeah

[sinful chasm]

so you understood till here right

[harsh belfry]

f'(g)

so x+3 is g(x)

[sinful chasm]

yep

[harsh belfry]

and f' is x

oh ok ok ok

I thought I was looking at like a single expression

I was so confused

Sorry

[sinful chasm]

xD okay

[sinful chasm]

so you got till here

we're essentially doing the same thing in xy

but we're taking y=(x+3)

[harsh belfry]

x'(y)+x(y)'

[sinful chasm]

exactly

[harsh belfry]

alright

[sinful chasm]

now

when you differentiate y

you get?

[harsh belfry]

when differentiating y wrt x

i get dy/dx

[sinful chasm]

yep

[harsh belfry]

right?

[sinful chasm]

perfect

[harsh belfry]

so

[sinful chasm]

when you differentiate x?

[harsh belfry]

x'(y dy/dx) is the left half

right

[sinful chasm]

one se

[harsh belfry]

or would i just write it as dy/dx

[sinful chasm]

just dy/dx

but look

[harsh belfry]

x'(dy/dx)+dx/dx(y)

[sinful chasm]

but the ' usually means differentiation

so replace the x' with differentiation of x

and y' with differentiation of y

[harsh belfry]

OOPS

dx/dx(y)+x(dy/dx)

my bad that should be good right

[sinful chasm]

yep

[harsh belfry]

alright cool

[sinful chasm]

but dx/dx is 1

[harsh belfry]

yeah

so 1(y)

[sinful chasm]

so you just get y+x(dy/dx)

yep

so thats how you differentiate xy

[harsh belfry]

y+x(dy/dx)

nothing else I need to do?

[sinful chasm]

no

thats d(xy)/dx

[harsh belfry]

just making sure btw

in the question that the guy had in the video

[ocean seal]

tranfi

[harsh belfry]

he was given

[sinful chasm]

yep

so

[harsh belfry]

so I would use power rule on x^2

2x

[sinful chasm]

yep

[harsh belfry]

then I would differentiate 2xy

using the method

[sinful chasm]

product rule

[harsh belfry]

which would look like this

(2x)y

2x'(y)+(y)'2x

written as

[sinful chasm]

yeah

since 2 is a constant you can take it out of d/dx also

[harsh belfry]

oh ok

a little confused on how that works actually

[dreamy bone]

pls someone pls do algebra for this?

[harsh belfry]

so the derivative of 2x using this method is?

2*d/dx

[dreamy bone]

I got the multiple choice correct but on paper I'm not able to do it

[harsh belfry]

hmm I think I have to write this out to understand it second

[sinful chasm]

$\frac{d}{dx}\left(2xy\right)=2\frac{d}{dx}\left(xy\right)$

[ocean seal]

tranfi

[sinful chasm]

check the values for which the function is invalid

[harsh belfry]

second writing it out

[dreamy bone]

I did (x-1)(x+2) >= 0

and so x>=1 or x>=-2

[sinful chasm]

thats when it is valid

[dreamy bone]

which is not true...like x should be <= -2

[sinful chasm]

it will be invalid when (x-1)<0 or (x+2)<0

but if theyre both negative or both positive itll be a valid function

[harsh belfry]

is this the written out form of

does that look right?

[sinful chasm]

yeah but youre missing a d

[harsh belfry]

oops

\

now in order to combine these

dy/dx which is y'

is 1

[sinful chasm]

dy/dx is not 1

[harsh belfry]

oof

[sinful chasm]

dx/dx

[harsh belfry]

oh ok

but the 2 remains right'

[sinful chasm]

yeah

you can take it common

[sinful chasm]

perfect

[bleak ingot]

Hi. I need help. How do you calculate the length of any shadow casted by an object of known size being illuminated by a source at a known altitude and distance? Do you have some clues or terms you can give me to make my search on Google easier? I don't have a formal education on maths. I appreciate so much any help you can give. Thank you. (sorry my English)

[harsh belfry]

anything else I can do here?

or is that as far as it gets

[sinful chasm]

you need to use trigonometry i think

[bleak ingot]

That's for sure

Something more specific? Thank you 🙂

[sinful chasm]

you can take 2 common but thats all

[harsh belfry]

so I can divide everything by 2

and i'll end up with

[sinful chasm]

yeah but you cant just divide it

keep it common

[harsh belfry]

common?

[sinful chasm]

like

2(y+x(dy/dx))

[harsh belfry]

oh factor

[sinful chasm]

o ya that

[harsh belfry]

is the derivative of 2xy

i think I got it

thanks tranfi for bearing with me

[sinful chasm]

im not sure about this

[harsh belfry]

im real slow

[sinful chasm]

no problem

i was slow too lmaoo

youll get it with practice

[harsh belfry]

It really doesn't seem complicated, just different

I really need practice.

exam is on thurs

pretty cool

😅

[bleak ingot]

Thank you for replying your best 🙂

[broken belfry]

help ?!

[dreamy bone]

ok so this is an interetsing one

how would one nail this

??

[harsh belfry]

@sinful chasm just wanted to make sure

my derivative of the whole expression is

[dreamy bone]

I'm getting -x + 4pi

[dreamy bone]

subbing x into the equation gives me -3pi

[broken belfry]

which x is it ?

[dreamy bone]

then the gradient equation is 2cos(x) - 3

[dreamy bone]

dude angle 9 + angle 10 is just 180 degrees

so combines those equations, equate it to 180 and you got your answer

[sinful chasm]

check the last term

[broken belfry]

ummm dude i dont even know whats 9+ 10

[elder glacier]

?

[sinful chasm]

differentiation of y square is not 2y

[broken belfry]

um here is the writing question of the question "The value of the unknown variable x in the figure and illustration"

[dreamy bone]

yeah

angle 9 + angle 10

its a straight line

[broken belfry]

so that means 55 ?

[sinful chasm]

hes right

it should be (2x-4)+(2x+4)=180

[sinful chasm]

look

[broken belfry]

man there only 3 options 55 ,45 ,36

so idk here

[sinful chasm]

so

the angle 9 and angle 10

make a straight line

the angle of a straight line is 180

now you know the equation for 9 and equation for 10

https://i.imgur.com/X8IZfvZ.png

[sacred sapphire]

4x = 180

[sinful chasm]

yep

[sacred sapphire]

x = 45

cuz 180/4 = 45

[broken belfry]

but what about that line

[harsh belfry]

@sinful chasm

[broken belfry]

OH UR A LIFE SAVER

[sinful chasm]

differentatin of 2y should be 2dy/dx

[sacred sapphire]

ye

[sinful chasm]

and also you can factorise 2 on both sides

[harsh belfry]

just making sure, whats your interpretation of what was done here

he somehow got -1

[sinful chasm]

the equation has y^2

[harsh belfry]

its derivative would be 2y right

[sinful chasm]

so he differentated the entire function

2y (dy/dx)

ive forgotten the logic behind it

its like

[harsh belfry]

my answer is still technically right

right?

[sinful chasm]

one sec

[sinful chasm]

okay so what this is doing is

differentiating the entire equation, and then factorising x and y in such a way, that you isolate dy/dx

[sinful chasm]

in this, your third term: 2y should become 2(dy/dx)

if its y^2, then it becomes 2y(dy/dx)

im not sure how to explain the second part Ive forgotten

[harsh belfry]

no problem

[hardy geyser]

https://gyazo.com/96ddf0830514a8deb8def202c2760ce8

wyh is this correct i got it right cause process of elimination but idk why

[harsh belfry]

based on what you've show me this should be true right

now I would just algebraically solve until i isolate dy/dx right

[sinful chasm]

noo

look

you differentiate x as x

like

you know how when you have x^3 and differentiate it

you get 3 x ^2

same thing here

I would suggest you watch some videos on differential equations on khan academy

[sinful chasm]

theyll help loads

[worn dew]

Find the quadratic function whose graph passes though the given points. Solve the problem on a sheet of paper
(1,1)(4,−2)(0,−2)

any body?

<@&286206848099549185>

[woeful pollen]

7. A machine depreciates in value each year at the
   rate of 10% of its previous value. However, every
   second year there is some maintenance work so that
   in that particular year, depreciation is only 5% of its
   previous value. If at the end of the fourth year, the
   value of the machine stands at 1,46,205, then find the value of machine at the start of the first year. (a) 1,90,000 (b) 2,00,000 (c) 1,95,000 (d) ` 2,10,000

[worn dew]

i see

C

[woeful pollen]

b

[wary jungle]

Given f(x) = x + 2 and g(x) = x-7, where is the function f(x)/g(x) continuous?

<@&286206848099549185>

[crisp grove]

@wary jungle first find where it isn't continuous

[wary jungle]

How do I do that

[crisp grove]

what are the point that might cause a problem

[wary jungle]

Cause a problem?

[crisp grove]

yeah

like for (1/x), x=0 is a problem

[wary jungle]

Ok you can’t divide 1 by 0 but i still don’t get what “cause a problem” is supposed to mean in this context

[opal cloud]

hi guys

can you help me

1220 divide 3

[stable plume]

hello

what is the answer

[formal panther]

rise/run

[stable plume]

what to you mean

I accidentally calculated right answer 😄

[alpine sable]

do you still need the ans?

[stable plume]

calculator says its 9

[alpine sable]

did you find f(x) ?

[stable plume]

but the "system" says the answer is 18

[stable plume]

says but no

yes

[alpine sable]

what did you get ?

[stable plume]

9

f(x)=9

[alpine sable]

huh?

f(x) should be interms of x

not a constant

when x=3 you are getting f(x) = 9?

[stable plume]

hi dude how the laTex work

[vale wigeon]

#latex-help and #latex-testing

[crisp grove]

$\text{like this}$

[ocean seal]

Ryuzaki

[vale wigeon]

don't badger random people

[stable plume]

ok ty

[harsh belfry]

I don't use LaTex, I have a math type and hand writing program I use

I usually do work on my tablet with my pen , I switch to typing to screenshot for discord.

(I try not to subject people with my shitty handwriting)

[stable plume]

ok

[formal panther]

idk

bruh istg gradient midpoint and distance is coming in my test its soo hard 😭

[stable plume]

yo

new try

just trying to solve this

Whats wrong?

[alpine sable]

Isn't this the correct derivative?

[stable plume]

the idea is to calculate the area of that integral and then multiply by three, right?

[crisp grove]

your answer is not 9

[stable plume]

what is my answer?

[alpine sable]

Yeah, so you can basically factor out the 3, and find the definite integral of the function x with respect to x

[stable plume]

and the answer is?

[alpine sable]

Then multipy by three

[stable plume]

answer is 9?

I accidentally calculated right answer by using g(x) not f(x). first calculated area then multiplied it by three. With f(x) function the answer is 9. Thats why this is so confusing for me

[alpine sable]

Yes the answer is 18. Because the area under the red line is 2×3=6... that's the definite integral... Then it's upscaled up by 3 so that's 18

[stable plume]

isn't triangle area 2*3/2

[alpine sable]

Lol, yes...omg I'm so rusty

[stable plume]

yeah 😄

[alpine sable]

Forgetting basic math

So used to algebra now

😫

[stable plume]

why the answer is 18? I dont get this. This should be the easiest one

:DDDD

[alpine sable]

Sorry, it should be 9 if we use half base times height...

[stable plume]

yeah, i agree

[alpine sable]

Wait... I figured it out

[stable plume]

here example

[alpine sable]

So under the red line, there is actually a trapezium

So you have to use the area formula for a trapeziod

[stable plume]

why

oh

no i got it

lol

stupid mistake

[alpine sable]

Yaassdd

[stable plume]

X----------------D

[alpine sable]

👍

That's it.😄

[stable plume]

yep, thanks

[alpine sable]

So that's, half the sum of the parallel sides × vertical height

Them scale the result by three

And that's your definite integral

[harsh belfry]

I was trying to learn the implicit derivatives

this actually turned out to be the answer

thats the key btw, I havent finished the work yet

Still not sure how to get that answer

[alpine sable]

That's actually correct. So using the image I sent, just make dy/dx the subject of the equation

Transpose it and see

[harsh belfry]

ah so do I literally just use power rule

[alpine sable]

Yes

[harsh belfry]

then make dy/dx the subject

[alpine sable]

Yes

[harsh belfry]

wow

I thought this shit was way more complicated

[alpine sable]

It's not that bad, huh?

Lol

[harsh belfry]

so in this one

Im assuming under that principal

I would have:

[alpine sable]

Let me get a pen and paper 😄

[harsh belfry]

1/2(xy)^-1/2=7x6y(dx/dy)+0 (not counting 0 obviously)

I'll write it out in an app to make it easier to see

[alpine sable]

Wait, I hope you are using the product rule to differentiste x^(7)•y

[harsh belfry]

then solve for dy/dx

is there any chance you could help me clear it up on how I do that

[alpine sable]

What app u use to write the equation

[harsh belfry]

notepad with a black background

[alpine sable]

Clear up what exactly?

[harsh belfry]

in this scenario would I differentiate the x^7y like this

[alpine sable]

I am using an android RN. Is in playstore?

[harsh belfry]

nah its a program that came with my touch laptop

[alpine sable]

Ok

[alpine sable]

No. Use product rule

[harsh belfry]

f' 7x^6

right?

and g (1)

[vale wigeon]

no, g' is dy/dx.

[harsh belfry]

got it!

ok

[alpine sable]

Great

[harsh belfry]

then this right

and just simplify?

[alpine sable]

Thanks @vale wigeon for pitching in😄

[alpine sable]

Yup

[harsh belfry]

once I do that I will have

[alpine sable]

Yes

You need to also differentiate the left side of the equation

[harsh belfry]

can you show me what you mean

[alpine sable]

This...

Differentiate both sides

[harsh belfry]

ah yeah of course

will do

[alpine sable]

Okay.

Then you can make dy/dx the subject.

[harsh belfry]

i think

I now need to solve for dydx

[alpine sable]

You need to use chain rule on the left side of the equation

Which utilises the product rule

[harsh belfry]

n(f'(g)^n)g'

ah i forgot

xy inside the paratheses will need a derivative when i find its being chain ruled

got it

I gotta head out in approx 10 mins to drive to school though

thanks a bunch!!

you cleared it up for me real well

I think i finally get it

not that bad

[alpine sable]

No problem. Anytime. 😄

[slim fog]

How can we be sure that the limit approaches the value that we think it does?

[vale wigeon]

by presenting a proof, via the epsilon delta definition or otherwise.

[alpine sable]

Graphing the function usually does it for me 😄

[rapid sundial]

Graphing it, or try nearby values on both sides

[crisp grove]

u can't graph exotic functions

[dull onyx]

how do i prove e^x+x-1 is increasing

😵‍💫

[minor yacht]

How can I test what kind of eigenvalue a matrix has?(real, complex, repeated/distinct)

[crisp grove]

derivative

[crisp grove]

by calculating them?

[dull onyx]

mhm

ok so e^x + 1

[minor yacht]

there is no shortcut for this, right? unlike when finding if a matrix has multiple solutions you can use determinants

[crisp grove]

I won't say there is no shortcut

[alpine sable]

The angle between the hands (minute and hour) of a clock at 8 minutes past 4:00 pm is , can someone help if this channel is not occupied

[crisp grove]

depends on you matrix, like if it's symmetric it'll always have real EVs

[minor yacht]

if its not, i have to do the long method?

[dull onyx]

so do i set the derivative> 0

[crisp grove]

@minor yacht what kind of matrices are we talking about?

[crisp grove]

you don't need to set, it's always >0

[minor yacht]

square matrix

[dull onyx]

thanku<3

[dusky bluff]

If the matrix is symmetric then eigenvalues are always real

[minor yacht]

how can i know if its distinct or repeated?

[crisp grove]

to have a repeated eigen value it must be a constant multiple of the identity

if you isolate the rows and columns where the EVs are same

[minor yacht]

sorry im not able to follow
do you mean when one is (x-lambda)^n?

when there is exponent?

[crisp grove]

say for 2x2 symmetric matrix, it'll have a repeated EV (say m) iff the matrix is of the form $mI_2 = \begin{bmatrix}m&0\0&m\end{bmatrix}$

[ocean seal]

Ryuzaki

[dull onyx]

ok well im confused again😒

[minor yacht]

i see

thank you

[dull onyx]

😵‍💫

[crisp grove]

@dull onyx?

[dull onyx]

idk how im supposed to solve that

[crisp grove]

is it the same question?

[dull onyx]

its the same one but it has like different questions in it

its a different section doe

[crisp grove]

show the Q

[dull onyx]

its in greek

[crisp grove]

can't make anything out of yr handwritting

[dull onyx]

omg

thats an λ

like a variable😭

[crisp grove]

and the other one?

[dull onyx]

and a 1

and a 0

and an e

[glass lichen]

what's the alpha?

[crisp grove]

that's 1

[dull onyx]

wheres the alpha at

[glass lichen]

lambda + alpha

[dull onyx]

im cryin

thats a one😭

[glass lichen]

🤨

[crisp grove]

find it numerically

[dull onyx]

-1 innit

[glass lichen]

yes

[dusky bluff]

The value of lambda is -1

[glass lichen]

lambda=-1 is right

[dull onyx]

thx

[crisp grove]

first one is easy

show 2nd one via contradiction

[silk terrace]

My argument for the first one is that Q is countable and thus the cart. prod. of Q x Q is too

[crisp grove]

@wet cove busy channel

[crisp grove]

works

[silk terrace]

but I am not using the fact that u-v is in Z

[wet cove]

to channel 1 i go 😭

[crisp grove]

your set is a subset of QxQ

as the latter is countable, so will be the first one

you don't need to use u-v\in Z

[silk terrace]

okay so first one is done in that case. For the second one I am thinking that x-> (x,x) injects R into my set. so the set can not be countable as it contains an injective image of R

[crisp grove]

nah it'll work

[silk terrace]

so first one has an injection from Q into the set in question and this one has an injection from R into the set in question so that it can not be countable

[silk terrace]

okay so that is all I have to do right?

[crisp grove]

yeah

if it work's don't change it

[pliant barn]

Are physics questions allowed ?

[dusky bluff]

First one

[crisp grove]

STOP FKING GIVING OUT ANSWERS

[raven rover]

^^

[wet cove]

nah i answered that like 2 mins ago on my own 😎

but thank ypu for confirming

[ancient agate]

How do I prove B has the winning strategy if G has a perfect matching ? I’m so stuck, and apologies if channel is in occupation

[crisp grove]

stop asking yr exam questions here

[ancient agate]

me?

[crisp grove]

@ancient agate no not u

[ancient agate]

oh, nvm.

[crisp grove]

#discrete-math

[pliant elk]

help with 10ii) pls

[ancient agate]

@crisp grove Oh, didn’t see that channel, I’ll head my way over there. Thanks

[crisp grove]

@pliant elk separate it out

[pliant elk]

i have

[crisp grove]

then why are u stuck?

[pliant elk]

cant get the answer into the fully factorised form

and the mark scheme is BS

😩

[crisp grove]

show yr work

[pliant elk]

oke

[crisp grove]

@pliant elk -4n²-n² ≠ -3n²

[pliant elk]

yes

pls kill me now

[crisp grove]

@pliant elk avdakadavra

[ancient agate]

happens to the best of us

[pliant elk]

still dont know what to do

😦

rip

[crisp grove]

u need to do some hardcore math there

nothing I can do

[ancient agate]

Is it rude to ping helpers after 15 min ?

like even though we’re allowed ?

[glass lichen]

??

Why would it be rude

[ancient agate]

well I am pinging over 30 people

27 sorry.

[glass lichen]

#❓how-to-get-help if you don't know....

[rigid smelt]

well tbf, they were the one who decide to get the roles themselves

so they knew they would be pinged

just dont ping before 15min

[ancient agate]

fair enough, thanks guys.

[iron loom]

(-1,3) (5,-4)

did i do this right

[slow quartz]

Hey. Trying to review something from an article here:
I am stuck here solving for r.

Multiplying both sides with (1-r) to cancel out the denominator

from there on I am a bit lost

[alpine sable]

Since the denominators are the same, why not start by rewriting the fractions on both sides with the one denominator.

Maybe you'll see something afterwards🤷‍♂️

[slow quartz]

so that I get: 0.3*6000^(1-r) + 0.7 * 4800^(1-r)/1-r = ..

so just one denominator on both sides, is that what you meant?

[alpine sable]

you can get rid of 1-r in the denominator easily

take all on one side of the equation

and then proceed

[slow quartz]

Yes, this I Know

[alpine sable]

try taking as many things common as you can

[slow quartz]

I can multiply both sides by 1-r

I really get stuck on how to get 1-r from the exponent so I can solve for it? With logs it became a total mess

[alpine sable]

lemme try lol

I simplified that to

$0.3[40^{1-r} - 77^{1-r}] + 2^{1-r}[16^{1-r} - 1]$

[ocean seal]

omsai

[slow quartz]

Hmm

I'm so bad at simplyfing lol

This is where it stops for me usually

[alpine sable]

solution literally is r=1 🤣

[slow quartz]

lol, this is what I came to using programming too

[alpine sable]

well

[slow quartz]

This is driving me crazy

[alpine sable]

okay one second

lemme try once again

[slow quartz]

so this is from the article where I am trying to replicate

[alpine sable]

nvm my simplification was wrong

[slow quartz]

It comes from this utility function:

$U(x) = x^{1-r}/1-r$

[ocean seal]

olafg

[alpine sable]

nah r=1 is a extraneous solution of the equation I got

so yeah doesn't work

other simplifications are quite bizarre

[slow quartz]

Haha

[alpine sable]

wolfram alpha btw

[slow quartz]

tried there too

I was never able to arrive at 0.49

[alpine sable]

where did you get this question

[slow quartz]

It is from an experimental economics research paper

or, published article if you will

[alpine sable]

economics

I am done

🙂

[slow quartz]

Lol

[alpine sable]

Economics guys are meant to use computers for calculations (if I am correct)

[slow quartz]

for advanced stuff I guess, but I don't get why this is so hard

[alpine sable]

probably because the solution is not really some irrational like a root or a square root

or something

Lol not sure if this can help 🤣

Do with it what you wish🤣

[slow quartz]

I ended up in a similar point in one attempt too lol

[alpine sable]

I don't think I'm going to go any further than here 😅

My poor brain

if it were a whole exponent

It would be damn easy

lol

[slow quartz]

This is what I am trying to solve basically

W = 0

"The unknown parameter r is identified by the probability 1p at which the subject is
indifferent and can be obtained by solving equation (1) for r. "

https://tenor.com/view/angry-andre-sitolini-engetic-butthurt-gif-14985012

[alpine sable]

as a high schooler, with my high school stuff, no.

[slow quartz]

lol, dude, you are a champ

this is graduate stuff lolll

[alpine sable]

lmfao mb

[alpine sable]

If you do this in high school then I should be learning from you.

[slow quartz]

but a lot of the time I get stuck on this shit because I didn't pay attention to math in high school adn before

[alpine sable]

I dont really think you can do much with this using high school math

I never come across this and I'm studying math education

he said this is economics stuff or something

[slow quartz]

yeah

[alpine sable]

Oh, well. That's a whole different ball ground I rekon

[slow quartz]

maybe it should be in advanced I dunno lol

[alpine sable]

does it say 1p or p_1?

[slow quartz]

p_1

just bug copying from PDF

[alpine sable]

yeah

[viral lagoon]

needs sum help with this

[alpine sable]

@viral lagoon This is asking "is the line r perpendicular to the line s?

and u is

$U(x) = x^{1-r}/1-r$

[ocean seal]

omsai

[alpine sable]

right?

[slow quartz]

yeah, but dude, don't worry about it

[alpine sable]

I found a way to kill time

[slow quartz]

if you are in HS it is too much to ask

[alpine sable]

so yeah

[viral lagoon]

I know its perpendicular but idk how to solve it

[slow quartz]

help someone else xD

I will read more articles and see if I can figure it out

[alpine sable]

if i could help myself

[alpine sable]

There isnt much to solve really.

[viral lagoon]

idk how to do it

[alpine sable]

Okay. Tell me if you think it is.

[viral lagoon]

I need like a walk thru cuz these teachers won't help

[alpine sable]

Ok

When two lines are perpendicular, they form right angles to each other.

Do you think line r and line s fit that criteria?

[viral lagoon]

yea?

[alpine sable]

Doesn't seem as if you are sure.

[viral lagoon]

im not

[alpine sable]

Okay. Would you say that the vertical lines that make up the grid form right angles with the horizontal lines that make the grid?

[viral lagoon]

ye

[alpine sable]

thats it you're done

Exactly

[viral lagoon]

o

[alpine sable]

Would it be safe to say that the lines s and r lie perfectly on the grid lines?

[viral lagoon]

yes

[alpine sable]

And do lines r and s intersect perfectly as the grid lines do?

[viral lagoon]

yes

[alpine sable]

Since the grid lines intersect at 90°(right angle), and lines r and s intersect in a similar manner, then QED

here's my perspective

They are perpendicular

The grid is composed of squares

squares have right angles

[viral lagoon]

yep

[alpine sable]

each unit of the line constitutes a side of the square, hence the angle between the intersection is 90

Love that perspective too

angle is a square lmfao

typos

[harsh belfry]

Hey vocalone refering back to this msg. I currently have 3(4x^2+9y^2)=dx/dy

[viral lagoon]

thanks men

[harsh belfry]

But I'm not sure how to continue. now

I have factored out the three but how would I get this answer

[alpine sable]

You didn't need to factor out the three though

[harsh belfry]

Ah then what should I do?

-4x^2

[harsh belfry]

OH

[alpine sable]

So let's go back here

[harsh belfry]

-12x^2

/9y^2

?

[alpine sable]

-12x^2/27y^2

[harsh belfry]

Got it got it

Thanks!

I'm dumb

[alpine sable]

No, you're not. Just simple mistake.

It happens

Oh, and even if you factored out the three, you would have to divide both sides by three to get rid of it. Then you would transpose.

[ocean seal]

fall

[storm lava]

perhaps you should use the (a+b)^3 formula, (k+1)^3 in this case

and then some inequalities using n>=10 perhaps

that's what i think from the first glance

[alpine sable]

That's what I have so far

break this into parts

[storm lava]

you already know that k^3 <= 2^k

[alpine sable]

Maybe you'll have to do some kind of substitution

Right

Discrete math is the worst 😅

[storm lava]

maybe i'll try to solve it on paper

[alpine sable]

I added that last part

I too don't know where to go

[night minnow]

hii i just got here. i have a question d:

do any of you know how to convert binary to a hexadecimal? its complicated i know

[alpine sable]

It is a little trickly

Let me see

I haven't done it in two years

But let's see what can happen

[night minnow]

cool lemme get it

[storm lava]

they are

(

[alpine sable]

Trust me... I Am not a fan

Lol

induction proofs are usually pretty chill

[night minnow]

ok so i get how to do this thing, but the problem is that this example has a subscript on it and it wasnt shown how to convert it to a hexadecimal with a subscript on the binary

[alpine sable]

Lol I wish I could "induct" properly 😅

[night minnow]

did that make sense lol

[alpine sable]

The subscript 16?

[night minnow]

nono, the one on the given

[alpine sable]

Ohhhh

[night minnow]

11110110 subscript 2

[alpine sable]

yea

you have to assume n big enough for it to work

it doesnt work for n=2 for example

[alpine sable]

I started with induction just today lol

your base case should be n=10 not n=1

and breaking the problem might help

[storm lava]

@inner bolt this works I suppose

[alpine sable]

$2*2^n > 2n^3$

[ocean seal]

omsai

[alpine sable]

What did you get when you converted into base 10

[night minnow]

wait can you explain it in a simpler way? im pretty dumb