#help-39
1 messages · Page 246 of 1
I got the complete wrong answer
can you show your work? 
The answe should be minus plus 3 I got this
Wait
It’s a bit messy cause I ran out of space
Oh my god 💀

Wait ill retry real quick 😭
To avoid errors like this, its better to start with the simple stuff (such as addition)
Why so mess when world gives u paper
Cause I’m crazy lol
now youll have to do just one multiplication
Oooooh
Yeah I have a test tmr I should keep this in mind thank you 🙏
just make sure starting with addition doesnt break PEMDAS or sth
here its completely fine, cause we are just doing the same thing to both sides
What’s pemdas
order of operations
Parentheis exponent multi and...
Ooooh
Sorry englihs isn’t my first 💔
Wait I’m gonna retry it rq
Okay i got a answer
Do any of you have any tips on how I can remember to do the minus plus symbol when the exponents are not odd
I keep forgetting all the time
And if I do a really hard question and get it right and don’t add the minus plus o don’t get the question right and I’m really struggling with remembering 🙏
I used to keep a list of things i constantly forget
Ig u mean u forget symbol of the term whrn there is power2 or 3 or 4 like that?
just by writing it down before the test and reading it, i then remembered all of the stuff
I feel like when I finish the question I forget the last step of adding that little symbol
why are you writing like that
lol no that’s how I write
🤔
Paper crisis
U like it organised and cramped together
Trust I have a lot I just like who it looks like this 🙏
Even i asked that to her
Show ur working for que
write horizontally
writing equations horizontally must be pain
like just move to the next line after you run out of space horizontally
Ohhhhhhh
But like this I can look back to find questions easily
If I wrote horizontal I would look for hours
Do you actually solve equations horizontally?
That’s scary
that's crazy
latex i use \begin{align*}
i had never seen that before
Are we discussing the que ever pls?
I just seen people write all over the place and
that's me
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When a math problem says "rate of change of y with respect to x" does it essentially just mean the slope?
wth
Spammer.
Yep
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If a car passes three traffic stops that show red 60% of the time and green 40% of the time what’s the probability of the car passing a red one at least at one of the traffic stops
Find the probability that the car does not pass any reds first, then get its conjugate
I dont want to answer straight up but since we do not know if stops are synchronized or speed of the car its probably 6/10 times 6/10 times 4/10
Fricking dc
Hold up
Lol take ur time
What is the probability that the car hits two greens* in a row?
Why two 6/10
I put * to show multiplication and dc turned it into new font
60/100 possibility of them being green
Yes
Is this like a beginning question
It just asks what the probability of it passing at least one red traffic stop is
After sayinf he passes three
And that they are red 60% of the time and green 40% of the time
Oh
I am sorry
If it is red at least one of them
Then things change
I didnt quite read the question
I thought red on the last one only Idk why
Shoot I forgot how were we doing these
^
I remember nothing about combination
Well this also works
So 6/10 times 6/10
For the car to not pass any red, it must be G-G-G
What is the probability that that happens?
Ohh so 4/10 times itself three times
exactly
there's a mistake here
Yeah, 64/1000 or 0.064. That is the probability that the car passes through a green light on all three lights.
Now, logically, if this doesn't happen...
It must end up passing through a red at least once
1000-64=936 which is 93,6%
Yeah exactly
happens. the conjugate trick (find the odds of the thing not happening) comes up often. you could solve this without it (ie. add 0.6 * 0.6 * 0.6 for RRR, 0.4 * 0.6 * 0,6 for GRR and so on) but it would take ages
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I don’t understand what’s going on
I thought
Maybe I was gonna do the whole sum times the interest rate and then divide it by the amount of months
But the answer is completely different
<@&286206848099549185>
Anyone? 😭
Anyone know how many times I’m allowed to ping..
ones
wait until someone who knows helps you
if i could i would 
How
Question plz
Did you ai search
we dont recommend ai
Ok
🥲
I think it was 60
- equal
- monthly
- 5 years
yes correct
oh wait i think i did the wrong thing when trying to solve through this myself 💀
nvm
do you know the formula?
💀
I BEG
^
are you sure?
in notes
Coming on the test
high
I mean come onnnnn
this is pretty common
DONT SAY THAT
do you have lecture notes?
No we haven’t been through how to solve this
It’s preparations for final math exam tomorrow.
yea but if it’s on a practice test that they gave you then surely you would have done something similar by now
maybe you saw this version?
it’s the same thing
r/n = i
where did you find the practice test
My teacher sent it out and said that the test won’t have anything that’s not on these sheets
hmm
i don’t see how you’re going to do this without having these formulas
😭
these aren’t easy to derive
I’ll skip it thanks anyway 🙏
🤷🏼♂️
check your lecture notes or something
should be in there
what was the answer btw?
@stone imp Has your question been resolved?
It was 500 on A and 6250 on B
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oh wait this is simple?
that’s just from principal payments then?
well you have 300,000 principal (before interest) and 5 years so 60 payments so 300,000/60 =5,000
i think you meant 5000
this formula incorporates interest
so if you wanted equal payments while considering interest
youd use that
Oh god
but since you’ve never seen it i think it’s safe to assume you won’t
well now for part b you have the annual interest rate but we want the monthly
so divide it by 12
Yes
and then do you remember the formula for interest?
simple interest here
guess not
I = P * r * t
t here is in months
and we just adjusted our rate to be the monthly rate
^
then since you only care about the first month you let t = 1
where P = 300,000
Ohhh
,calc 300000 * 0.05 /12
Result:
1250
then add that to the answer from part a
which was the principal
to get the total payment
@stone imp make sense?
can i close this?
Then I add 5000?
yes
I get it tysmmm
lol no worries
nah it’s my channel i have to close it
Oh right
.close
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Using "g(A)" instead of "f^{-1}(A)" 
sorry what?
The set they're calling g(A) is basically the set of all things that when you apply f to them, they "land" in your set A
(it's just me complaining about them using non standard notation, usually this set, the preimage of $A$, is denoted by $f^{-1}(A)$)
@merry carbon
huh oh...i sort of understood that..
so how do i find g(S)?
i agree this notation is not common where i study either which is why im struggling to understand it
In this case, for S as what they gave you, you're considering the (real) numbers such that when you square them, they're between 0 and 4 inclusive
yeah so f(S) = [0,16]
g(S) = {x belongs to R,f(x) belongs to S}
Oh
are they just trying to say g(S)={f(x) belongs to S}
that x belongs to R is kind of irritating
ohk
thanks man
just needed to familiarize myself with the notation
For that, they're just trying to be a bit more clear, so that e.g. you don't start including complex numbers
oh right
Without them specifying that, then asking what g([-1, 0]) is will depend on whether you wanna include complex numbers, or not (if you don't, it would just be {0} only)
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A question on geometric method for first order pdes
Wifi is dying I’ll be back 😭
I tried understanding why u(x,y) = f(bx-ay)
But my brain keeps thinking u(x,y) = bx-ay should be the general solution
<a,b> dot <ux, uy> = 0 implies directional vector is is 0, i.e u must be constant along lines parallel to <a,b>
I derived that the set of lines parallel to <a,b> follow bx-ay = c
Now I'm sitting there staring at this diagram
if 1 of these lines is the particular solution, isn't the set of all lines the general solution?
i.e shouldn't the general solution of u(x,y) = bx-ay? why is it f(bx-ay)?

for any line bx-ay=c, we can pick the value of u on that line
could you go into more detail? my peanut brain isn't working :(
u(x,y)
=f(bx-ay)
=f(c) by above, bx-ay=c
f(c) does not change wherever you are on the line, i.e. f(c)=k for that specific c
k is constant
because c doesnt change, f(c) doesnt either
OH
the xy-plane is only the domain of u right
u is a 2-input 1-output function, so if you want to draw it, you need 3 dimensions
this diagram you're staring at only talks quite indirectly about the values of u, think of a contour plot
OHH I THINK SOMETHINGS CLICKING
FWKA
ITS CLICKING
wait it clicked :oo
thank u
weeeeeeeeeeeeeee
.close
Closed by @solar coral
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wait im actually so happy thank u guys i was losing it
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wait why doesnt $\sum_{n=2}^{\infty} \frac{1}{log n}$ converge
astral
cant you use ratio test which gives $\frac{log n}{log (n+1)} < 1$
$\log n < n \implies \frac{1}{\log n}>\frac{1}{n}$ for sufficiently large $n$, hence divergence by comparison test.
The limit of that is 1
ratio test is indeterminate
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yes it's a constant
.close
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What would be the integral of ( ((x-a)^n)/x ) dx where n and a are constant real terms?
Term by term integration on the binomial expansion
This feels sus
Yeah if n is real you have to invoke the infinite binomial expansion
@karmic pollen Has your question been resolved?
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Base graph*
If you have $y = 2^x$, then I agree with $(x, y) = \qty(-2, \frac14)$ as one of the points.
@earnest finch
The base graph before any transformations should be 2^x right?
Is this correct for after all of the transformations?
✅
Okay
It's annoying when your teacher does stuff wrong just cuz then it confuses you
Glad I caught it
Tysm 😊
Sorry it's messy
But is this graph correct
(obv my placement isn't perfect I forgot my graph paper at school)
You should draw a dashed line for your asymptote.
I’ll look at the rest in a few minutes, if no one else does.
Okay thanks
@silver oracle Has your question been resolved?
It looks about right, but you forgot the arrow.
Okay thanks
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I lost my chat so I’m just going to open a new one but how do I find the y values on the circle.
Please don't occupy multiple help channels.
How do I close the other one it does not appear for me
".close" on the channel
I cant find it it does not show up on the side bar for me
Now I’m even more extreamtly confused cus it says graph time as the vertical coordinate so the y coordinate but now we have two y values and no X values
We have the ft value which I don’t undestand what that value represents and the time value I understand but now that’s y instead of X but the ft cannot be y because it’s kinda like height but then it it not height
And I understand how to graph equations I have no problem with that
I just don’t know how to find the mad midline or min
All I need is one
<@&286206848099549185>
which part are you stuck on
I don’t understand how to find the mid max and min aka the points around the circle and Now I also don’t understand how to graph it because our period is in seconds. But now it says we have to put time units on the y axis. But in order to graph it I need the period on the X axis
I know the amp value the period and the b value
ok first of all it wants in the function for time, so time is the x axis and the vertical coordinate is on the y axis
So the X values are 0,2.5,7.5,10
you can see the max/min is at the top point and the bottom point
Cus it says “ sketch a graph of the vertical coordinate of Jada location as a function of tjme “
which happens at 1/4th and 3/4th of the rotation specifically
you wanted to know what the maximum and minimum of the function is no?
We still have to plot all of them tho on the circle
I mean yea but I also have to plot the main points around the circle
its continuous, it uses all the points, you wanted the maximum and the minimum as it was important to graph it yes?
actually for starters, do you know what the graph would roughly look like?
I need the 4 intersection points
I know what a sin and cos graph looks like
Idk what this one looks like yet tho
ok good
lets focus on the graph, can you fill in whats known with what information you have currently?
That’s all I have
I cant plot anything since I don’t have a min max or midline value
I know at 2.5 there will be a min or max, at 5 it will be at the midline, at 7.5 it is a mid or max value and at 10 it is on the midline
yes thats good
going back to this, what point would t=2.5 represent?
Do u know if we are rotating counter clockwise or clockwise
its given its rotating counterclockwise
2.5 seconds after the carasol started
So I think the first mid/max value would be max
so your saying when t=2.5 it reaches the maximum?
ok good
ok for t=5 it reaches the midline yes? what would the vertical coordinate be when t=5
Wouldent the height always be the same since it is a carasol
That’s where I’m getting confused
If I was thinking like it was a unit circle it would be -20
Wait
0
(5,0)
But that doesn’t make sense with the context of the story
ok i should probably change it to "vertical coordinate"
the vertical coordinate is refering to the y value of the carousel graph (the one thats a circle)
Yea
I have no idea what it would be
Cus if it was the distance away from the midpoint it would always be 20, if it was in terms of a unit circle one of the values would have -20 which does not make sense
when t=5, on the graph of the carousel do you know what point its refering to?
Yea it would be at pi if it was a unit circle
so this blue point right?
Yea
ok, what would its y coordinate be?
I thought it would be 0 or the midline value in this case
But I’m not sure how to get the midline
it is 0
20?
this point is the origin, as you can see the vertical coordinate of the blue point is 0
close, remember the origin is at the center and the radius is 10
Wait is says the radius is 20 tho
I highlighted it
this is correct
congrats
oh wait
for c, when t=0 the y coordinate is 20
Why?
The midline is 0 and the amp is 15
And we are on the midline so wouldn’t y = 0
for part c, t=0 is over here?
Oh wait whoops
Wait
What c r u talking about
There’s two question Cs
Wait
the one with noah
Wdym by t=0
when it starts, cause noah starts at N right
so his vertical coordinate when he starts (aka t=0) is +20
Oh wait he start at the max
So it’s a cos not a sin
Well it is still sin
But it looks more like cos while drawing it
Is this better
like you said noah starts at the max
but the graph shows that noah starts on the midline
He starts at the max at 2.5 since there is a shift
Oh wait I did it wrong again
perfect
@fading nexus Has your question been resolved?
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can someone help with SOPS, Sequence of Partial Sums, im in precalculus and this is how we are ending the year i cannnot figure out this problem and another
can you post a picture of the instructions?
i have the answer key if you'd like I understand sequences but the sum of the infinte series is very hard
are you given any indication of what the formulas for the sequences being summed here are? it doesn't seem especially clear from the terms
no, our instructions are find an expression for Sn, the nth partial sum, and then take the limit of Sn as n goes to infinity
oh in that case
sum the first term
the first two terms
etc.
try to find a pattern
i think that's why each term looks so contrived
yes but I can't figure out the pattern
for the first one: write each partial sum as a fraction (even the integer ones), see if that makes it clearer
sorry let me fix that
I think I have the wrong thing because they must be negative right
take out the plus signs but what you have is fine
ok see that 2/1?
can you rewrite that in an equivalent form that gives a pattern across the partial sums
what do you notice about S1 and S2, and S4 and S5?
oh the denominator goes up by 2
and the numerator?
4+(n-1)3 all over 1+ (n-1)2
what
and then distribute
oh yea
as n gets super super large what happens?
ok thank you man that's all the help I need how do I end this
type .close
.close
np
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<@&268886789983436800>
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4 (cos ( π - c)/4) .cos (( π -b)/4) .cos (a- π )/4 = 4 (cos( π -c )/4). cos (( π + b)/4) .cos (( π+ a)/4), is this true?
@muted sierra Has your question been resolved?
it does not hold for a=c=0, b=pi
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This is probably a wrong idea, but I was thinking each v in V can be mapped to that element whose abcissa is translated by v?
like each element in V/U is a set
so
$v \to (x, {v+U}); x \in U
but which x, specifically😄? right now as you have written it there may be more than one x, so your mapping will not be a function much less an isomorphism
I see the issue now, it is not a bijection
yea, I see the issue
as i see it, there is a natural mapping 🤔, namely:
||hint: something like (u, v+U) -> v + u||
well, you should atleast check it is an isomorphism😄 0) it is well defined 1) it is linear 2)it has trivial kernel 3) it is surjective
infact, there is a small problem with this as written which you need to fix
There is?
hmm
I'll think about this and reopen if required
Thanks so much!
.close
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hi can anyone find whats wrong with my working out
how is integral of cos(2x) = -sin(2x)/2?
thats wrong, remove the negative sign 😄
i think you have confused it with the derivative
It seems you wrote sin(π) = -1
ohhh yeah your right
sin pi isnt -1?
sin 0 is 0?
,w plot sin(x)
yes, to remember this you can imagine a right angled triangle with one angle going to 0
For integer multiples of π sin(x) = 0.
taylor expansion of sin x also gives you easy way to remember this
i lowkey just do hand thingy so when it comes to like 0, pi/2, 3pi/2, pi
i like imagine the circle
@swift spindle Has your question been resolved?
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i know the answer but i dont get how
what i thought it was was 120
because it says the ratio initially is 3 : 4 : 2
but then it says debbie gets 120
and then hers change from 4 to 5
so doesnt that me 1 = 120
and then chris gives 1 to errol
so 1 = 120
what is the total money that all have in the starting case
is that relevant tho
because the total money doesnt change
they only exchange the money right
what answer did you get
21
yep
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This question is just confusing me. Uniform circular motion in physics
period of an object in circular motion is the time it takes to complete one revolution
Yeap ive got that part
so answer for part a is given in the qn
yeah
ive done b and c but not sure if im correct
but d and e im really hazy on
b i got 0.7rad/s
c i got 1.6m/s for horse a and 2.9m/s for horse b
both are right
magnitude of centripetal acceleration is $\omega ^2 r$, $\omega$ is the angular velocity of the object in circular motion
do you know about this?
hmmm i think i recall
Learning about it at some point
So i use that for 4.
I get 1.127 ill round to 2 sig figs so 1.1m/s^2?
yeah
yes
to find the force apploied to the 50kg rider?
a is the centripetal acceleration
i got 100N
i recalculated the centripetal acclerationb ecause hes on the outer ring
correct
welcom
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Mathematics – Permutations and Combinations (Unit 6)
For Class XI, XII, JEE, BITSAT, Engineering Entrance.
For students from Class 11 to Class 12.
𝐷𝑒𝑓𝑖𝑛𝑖𝑡𝑖𝑜𝑛
𝐹𝑢𝑛𝑑𝑎𝑚𝑒𝑛𝑡𝑎𝑙 𝑃𝑟𝑖𝑛𝑐𝑖𝑝𝑙𝑒 𝑜𝑓 𝐶𝑜𝑢𝑛𝑡𝑖𝑛𝑔
𝐸𝑥𝑒𝑟𝑐𝑖𝑠𝑒...
Hi, do you have any questions to be solved?
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hey so i'm in ninth grade and i have a test on math coming up and i'm way behind. could i have some help?
!occupied
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||that what happens when you dont lock in||
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hey so i'm in ninth grade and i have a test on math coming up and i'm way behind. could i have some help?
send specific questions you're struggling with
@sweet gorge
i would like some help with goeagraphy
wrong server blud
Unless you mean geometry
yup
this then
could you teach me similar triangles?
oh ok
what is your current understanding
In Euclidean geometry, two objects are similar if they have the same shape, or if one has the same shape as the mirror image of the other. More precisely, one can be obtained from the other by uniformly scaling (enlarging or reducing), possibly with additional translation, rotation and reflection. This means that either object can be rescaled, r...
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Helo can anyone help me on how to draw the level curve i dont rlly understand
No way it's ryan gosling
Wait but I'm ryan gosling so who are you
oh wait nvm so do i just plug in random values for x and y and then plot it
you found y=6/x, level curve is a hyperbola
sure
the real ryan gosling
THANKS
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Is the inequality for the picture below: y≤-2/3x+2
Please check
Yes
,w y \leq -2x/3+2 graph
ok thanks
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My question is why do the different approaches give different answers? Is it because of the cancellation in the AM-GM square root, or have I missed a condition for it?
This one is for the calc approach and the bottom one for the am-gm approach
The ratios are different, so even if there was an algebra mistake we'd still get different surface areas no?
I can show how I get to each r brb
This is it for the calc approach
And this is the one for the am-gm approach
the inequality is x+y>=2sqrt(xy) for any real numbers x and y, yes?
no from the AM-GM approach we got h:r = 1:1, and from the calc approach we got 2:1, i.e. we got two different ratios/results form the different approaches
h = 2r for the method that used differentiating and h = r for the one that used the inequality
@sick grotto Has your question been resolved?
yea h=r is wrong because the assumption in AM-GM is x and y are independent variables. both surface areas have r as a variable in common.
Use V=1 to get an equation for h in terms of r before using AM-GM
I still get r = (1/pi)^(1/3) from it
oh i see. my suggestion doesn't remove the dependence on each other since 2/r still has an r in it
another approach would be to use a trick and switch the surface area to a sum of 3 terms using 2/r = 1/r + 1/r
see example 9 here: https://www.whitman.edu/Documents/Academics/Mathematics/2016/Greff.pdf
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not sure how to correct this or if i did this right
all the other theorems i cited are like basic properties of integrals and stuff like you can add integrals
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no
T(u) in U for every u in U
you need to out quantifiers for your variables
your statement doesnt mean anything without those
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Solve the functional equation:
f(xy) = f(x^2) + 2xy
Any progress?
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
Typically plugging some values of x or y in which simplify the equation is a good start for solving functional equations
try subbing vals in
let x = y
Good, that means there are no solutions
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given that i know the graph of the RHS how can i get conclusion about the following expression?
$$\frac{\text{sign}\left(k\right)}{j}\left(\frac{a_{k-500}}{2}+\frac{a_{k+500}}{2}\right)\stackrel{?}{=}\frac{1}{j}\left(\frac{a_{k-500}}{2}-\frac{a_{k+500}}{2}\right)$$
i have the following plot for RHS
Henry_quite_hungry
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@young gate Has your question been resolved?
im just learning about differentiation... this looks hauting, but fascinating, how many years does it take to learn this stuff?
in one dimension, its one semester
in multiple dimensions, 2 or 3 semesters
My first year doing this, it’s been quite painful
wdym multiple dimentions??????
theres 3d and 4d calc?????
if you're in Europe they start off first semester with proof-based real analysis
real analysis is just calculus with proofs and rigour
it does look painful and hard
oh im a year 10 in australia LOL
still in high school
so for the US you'd do the calc 1/2/3 sequence first, so 3 semesters
and then if you take intro to proof-writing in one of those semesters, you can take a first course in single-variable real analysis in your 4th semester
PERFECT
yeah okay so you'd have maths 1A and 1B at uni
that's basically calc + linear algebra both semesters
damn
then you'd have to look at your uni's availability for when you can take RA
i wanna do this stuff man
our uni sucks so we can only take it in 2nd year 2nd sem
oh...
1st sem we take intro to absalg
yeah um you can also take headstart
if you take maths 1A in Year 12, then you can take maths 1B in 1st sem
that allows you to take real analysis in your 2nd sem if you want to
check your uni's handbook of course for the exact prereqs
I didn't do high school in Aus but I basically did a version of this by taking maths 1A and 1B concurrently
if you have the ability it's not that hard
but yes they do teach you useful foundational knowledge
those courses are computational-focused but when introducing key topics, your course notes will have the full details of the proofs
oh and you'd probably be taking the advanced version of 1A and 1B which is going to be more proofs-focused
but if you don't want to you're not exactly missing out
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not a single person did this person for hw and my teacher re assigned it with hardly any help so idk what to do from where im at
ik the trapezoids lengths but then im stuck
okay so what exactly do you know?
Can you put every length you know in the diagram?
And every angle
made a triangle and did pythagorean
Result:
24.494897427832
well it appears to be incorrect
oh okay then
mb
yes
so use that to make an equation
perhaps label some side with x
I'd label this one
okay
now you can make an equation by comparing the ratios
once you figure out x, you can just use pythagoras to figure out VW
so in any problem like this is it the biggest radius over smaller radius
its more related to the sides of the traingles
wdym
the triangles are similar
if the smaller one has side lenght 10, and the larger one 15, the ratio must be 15 / 10
and in the same way, VY / VZ must also be 1.5
and VY / VZ = (x + 25) / x
use that to calculate x
ill have to go for a minute or two, try working it out
i will then check it
ok that works im about to change periods ty ill lyk what i get
,calc sqrt(50^2 - 10^2)
Result:
48.989794855664
i did sqrt5850 - sqrt650
Might I recommend:
VX / VW = 15/10 (similarity)
=> (VW + XW)/VW = 3/2
You have XW
51s xw?
It comes out to be 2root(600)
how do i get 51
Waht
im doing sqrt2600
Why
bc 50^2+10^2
Does this make sense ^^
VW comes out to be 2 × XW
XW is just the DCT and is equal to root(600)
why doesnt pathagorean work
whats dct
nvm im a dumbass
you just took the wrong sides
50 is the hypotenuse
i thought the top was the hypotenuse
10 is the leg
you should be doing VW^2 + 10^2 = 50^2
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Hello, I am no expert in Maths by any means and i am having a discussion with a friend who has a degree in mathematics. If this question is not meant for here that is completely fine. To put it into context (I will try my best), We have a population size of 10 (Because we are referring to a number of usages a key has in Escape from Tarkov, this room behind the key can spawn valuable loot that can be sold) and we want to find the mean (mean being money made per run to know if it is worth spending x amount on the key (28 million) and work out the average per key usage). My friend is saying that it is statistically accurate to have a sample size of 1 with a population of ten (ten being the maximum as there is ten uses of the key) due to the 10% rule. I am saying that the 10% rule would not apply to this size of a group. Happy to go into further discussion but I do not see why it is stastically accurate to have a sample size of one just because of the 10% rule? I have tried to keep it to a minimum, sorry for long message.
@somber locust Has your question been resolved?
@somber locust Has your question been resolved?
@somber locust Has your question been resolved?
@somber locust Has your question been resolved?
@somber locust Has your question been resolved?
you seem to be asking about when you can approximate the sampling distribution as a normal distribution
you can't assume that if n is small unless the population is distributed normally, which it is not here
the 10% is for sampling without replacement, though. in this scenario you're sampling with replacement so it's not relevant
you can still do statistics on this study, but not by the central limit theorem
Hi, thank you for your response, looking at what CLT means, I think yes, it wouldn’t apply to this study as the sample size is not large enough (from what I can understand). Are you saying he is using CLT when this would be the wrong maths to apply?
I do want to ask, what statistics can be done? I am not understanding why my friend insists that a sample size of 1 can be considered statistically accurate whilst trying to work out a mean when the population is 10. He starting pulling out graphs with confidence and margin of error but none of it seems to answer how can you work out an average when you only have one result and the 9 other results would have a significant impact on the actual mean as there are so many variables (some valuable loot might spawn, some might not, some are very very expensive and some aren’t)
Sorry for the long message, look forward to hearing from you
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Hi! I'm pretty laic in advanced math and till now I wan't agile in the average level math neither, but I would like to deepen my knowledge.
In short words: any idea how he calculated that?
https://www.psychologytoday.com/us/blog/the-skeptical-sleuth/201103/did-a-study-really-show-that-abstinence-before-marriage-makes-for
"After controlling for religiosity, length of relationship, number of sexual partners, and education, whether participants had abstained from premarital sex only **accounted for less than two percent of the variance **in sexual satisfaction after getting married. "
He's talking about the results of this research: Dean M. Busby, 2010 "Compatibility or Restraint? The Effects of Sexual Timing on
Marriage Relationships"
DOI: 10.1037/a0021690
The research has three tables with data I send in the attachment.
@dense arrow Has your question been resolved?
<@&286206848099549185>
bro i cant understand question
Uhm, okay, I can provide you more data or maybe clarify something? English is not my native language, so maybe I formulated sth wrongly.
mine too i m pakistani
I'm wondering what's the method Coyne used to conclude that the result obtained by Busby "accounted for less than two percent of the variance"
How does he know that it's less than 2% if in all the Busby's article that's written nowhere?
@dense arrow Has your question been resolved?
<@&286206848099549185> 👀
hi
.
that
@dense arrow Has your question been resolved?
I’m gonna guess this is anova
Anova looks at how much each factor contributes to explaining the variance in a data set
Hmmm, interesting
Thanks:) I'm reading about it
So it would be one-way Anova, not the one with replication?
Yea
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im looking for an accessible proof of the basel problem, something that wouldnt require digging deep into calculus and stopping at limits and series, does anyone have any ideas?