#help-0

1 messages · Page 630 of 1

ocean sealBOT
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Stallion

strong carbon
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@alpine sable

native temple
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oh distributive property

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How did I miss that

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I need to study matha gain

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again

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lol

strong carbon
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Let's move to an unoccupied channel.

alpine sable
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Ok

bronze spade
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Ok, I'm back

junior rock
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Yeah I think it is

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For 5 degree polynomial if they flipped

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It means 5 vertical asemptopes

bronze spade
#

I'm assuming you're working in R. In R a polynomial can have a maximum of 5 roots. Then if you take the inverse function of your polynomial, you'll have 5 points where the inverse is not defined, with 5 asymptotes

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but 5 is a maximum, it could also be 1, 2, 3, or 4 depending on the number of roots your polynomial actually has

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you got it ?

junior rock
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Wait let me show you the question

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@bronze spade he said this

bronze spade
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Are you talking about the invserse of reciprocal function ?

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damn, sorry

junior rock
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Yeah

bronze spade
#

Let's say you have a polynomial P

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are you talking about

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$P^{-1}$

ocean sealBOT
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allevmelc

bronze spade
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or

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$\frac{1}{P}$

ocean sealBOT
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allevmelc

junior rock
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Y= 1/x

bronze spade
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It does not make sense to me. What were the answers for linear and quadratic polynomials ?

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If they were respectively 1 and 2, then was matters is the number of roots your polynomial has

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Which can be a maximum of 5 in R for a 5th degree polynomial

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when I say R, I'm referring to

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$\mathbb{R}$

ocean sealBOT
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allevmelc

junior rock
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Shut up

tame shell
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yeet'd

deft copper
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is $\exists ! x \in X : P(x)$ equivalent to $\exists x_i \in X : \forall x_j \ X \setminus {x_i} : x_i \neq x_j \land P(x_i)$?

ocean sealBOT
quasi pulsar
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i went wrong somewhere towards the end according to the marking scheme

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maybe i’m just retarded but i can’t find what i did wrong, probably a simple mistake

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dark blue is step 1
light blue is step 2
pink was my answer

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i went wrong between steps 2 and 3

deft copper
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-3 * 3.5 is -10.5

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not 10.5

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hence C is 18.5

quasi pulsar
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always the easiest bit that’s catches u out !

deft copper
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yep

onyx flower
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how the fuck do you integrate xf(x)

ionic jewel
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integration by parts

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wait

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no

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not sure that actually ends up working

onyx flower
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im in ab i haven't learned how to do that yet

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the only "parts" i know is if its addtion or subtraction

ionic jewel
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u = x
du = dx

v = F(x)
dv = f(x)

xF(x) - integral of F(x) dx
xF(x) - second integral of f(x)

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think thats right

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where F(x) is the integral of f(x)

onyx flower
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nvm i get it

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its too easy

molten rose
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i found the three roots of z

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but i dont know how to do part b

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it does not happen to involve vieta's formulae by any chance does it

magic tiger
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all the people here do such complicated math while im in high school doing mostly basic things that i pick up easily

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bruh moment

onyx flower
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the only thing hard is knowing the names

magic tiger
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true

molten rose
magic tiger
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yes i know you're probably in college doing extremely complicated stuff while I'm just sitting here having no idea what u doing

onyx flower
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there is nothing abstract about math you can conceptualize things pretty easily by getting shown how to do it unless your doing some super specialize shit

mental prairie
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I think

magic tiger
mental prairie
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just treat z^(3k) as (z^3)^k

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makes sense?

molten rose
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de moivre right?

mental prairie
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and you know what z^3 is for each z_1 z_2 z_3

molten rose
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yes

mental prairie
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yeah so you know what w is in a+bi format

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where you know what a and b is

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then can you try expressing that back in Re^ai form?

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oh wait

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the power k thing is a bit of problem

molten rose
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so it's just 3z^(3k) ?

mental prairie
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yeah

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3(z^3)^k

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where z^3 becomes -1 -i

molten rose
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that was pretty simple, how did i even get stuck on this lmao

mental prairie
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it looks intimidating

molten rose
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deceptively so

mental prairie
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from like 30 cm away

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you lean in and squint

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and it goes away

molten rose
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well that and

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ive been awake for 13 hours

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my brain isnt really functioning

mental prairie
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13 is fine righhht

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its just close to sleep time

molten rose
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but i have to do some practice problems

mental prairie
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like 16 is usual time

molten rose
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unless i want to fail the test i have in 9 hours

mental prairie
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oh god

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good luck

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tbh sleeping is probs much more important

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is it only complex stuff in your test?

molten rose
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not at all

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it's my final Further maths exam

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I didn't take a single further maths class this entire year

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i literally started four days ago

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and now im suffering

mental prairie
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oh dang!

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why do you have the exam?

molten rose
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Hm?

mental prairie
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like you didn't take the class

molten rose
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well yes, but i couldnt drop the subject either

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by then it was too late

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Well I'm going to post another question

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I know about the integral tests for convergence

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but uhh, i don't see how to find the summation here

muted raft
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probably riemann sum

molten rose
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is it just the harmonic series?

mental prairie
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whats the height of the rectangle between (x-1)/n and (x)/n

molten rose
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the height < x^2 right?

mental prairie
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maybe but here it looks like they've used bigger rectangles

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so I did (x-1)/n and (x)/n

molten rose
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1/n^2 ?

mental prairie
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almost

molten rose
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okay im just blurting out random guesses

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let me think

mental prairie
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like the height of this rectangle

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or this one

molten rose
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(2/n)^2 right?

mental prairie
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maybe

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feels almost right

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look at the curve

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at 2/n the curve is at a height of ?

molten rose
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i messed up the parentheses

molten rose
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man this really looks like i dont know how to read a graph right?

mental prairie
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nah

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you knew, just had to ask yourself the right question

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which is just a lot of squinting and leaning in

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besides you're tired now and will be fresher at the exam

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branes run faster in exam halls xD

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okay so you know the height and can find the area of any one rectangle

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try seeing if you can add up the areas of all the rectangles, it looks like it'll be greater

molten rose
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so the series should look like = 1/n^2, 4/n^2, 9/n^2, ..., 1 ?

mental prairie
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9/n^2

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yeah those are the heights alone

molten rose
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the widths are just 1/n

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i'm sorry, what is the summation supposed to represent

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the heights or the areas?

mental prairie
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well lets look at the question again

muted raft
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You are trying to approximate the area under the curve using oversized rectangles.

mental prairie
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that integral down there is the area under the curve

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you want to compare that to smth

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and it looks like the areas of the pieces are more

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you've figured out the heights of the pieces

molten rose
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tbh the reason this is harder for me than it should be is because the only thing i learned for this topic was this

muted raft
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Shouldn't you be learning riemann sum before beginning integrals thonkzoom

mental prairie
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he's in school

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not uni

muted raft
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I mean that is literally how integral started

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from riemann sum

mental prairie
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yeah

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but schools aren't like that XD

muted raft
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so it usually makes sense to teach how stuff starts right?

mental prairie
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it does

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but schools aren't like that XD

muted raft
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F

molten rose
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we were taught the integration rules and then we were off to the races

muted raft
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typical highschool I guess

mental prairie
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have you not been through school ? 0-0?

muted raft
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Forgot about it I guess

mental prairie
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ahhhh

ionic jewel
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i learned Reimann sums before integrals

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well

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i didn't really but i did in school

muted raft
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It makes more sense to learn riemann sums before doing any integrals yeah

muted raft
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channel busy

molten rose
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lower and upperbounds for an infinite sum

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can be used to determine if the sum converges or diverges

mental prairie
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okay that makes sense

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but you don't need that for the question you have here

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here you need to know that the integral represents the area under the curve

molten rose
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right so where were we

mental prairie
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and as per

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you have to find the sum of the areas of those rectangles

molten rose
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the area of the rectangles was represented by $\sum^{n}_{i=1}\frac{1}{i^3}$

mental prairie
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almost

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veeerry close

molten rose
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and the area under the curve provides the lower bound for that area

mental prairie
ocean sealBOT
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AdorableDeplorable

mental prairie
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umm

muted raft
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no

mental prairie
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not exactly

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take a breather

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the height times base is area

molten rose
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im sorry but wasnt the area of each rectangle = (1/n)^2 * 1/n

mental prairie
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well isn't (1/n) constant?

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all the rectangles have the same height?

molten rose
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no

molten rose
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$\frac{1}{n}\sum^n_{i=1}\frac{1}{i^2}$ then

ocean sealBOT
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AdorableDeplorable

molten rose
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thats probably wrong too actually

muted raft
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yes it is wrong

mental prairie
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yeah the height gets smaller and smaller

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as i increases

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because you are dividing by a bigger number

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the height of the rectangle at 2/n was?

molten rose
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4/n^2

mental prairie
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and for 3/n?

molten rose
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9/n^2

mental prairie
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4/n?

molten rose
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16/n^2

mental prairie
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mhm

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5/n, 6/n, 7/n etc

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you know the heights at each point

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and you know the width

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can you fix this now?

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the area of the rectangles is......?

molten rose
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(i/n)^2

mental prairie
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very close

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one more factor...the width

molten rose
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but that's a constant right?

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we moved it out of the summation?

mental prairie
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aha yeah

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you can move it out

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that's correct

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so like

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1/n ( sum of { ( i/n)^2 } )

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I can't latex 😢....yet*

molten rose
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n^2 is a constant term too actually

mental prairie
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jaa

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you can pull that out too

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now you can do the rest

muted raft
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[\frac{1}{n} \cdot \sum_{i=1}^{n} \qty(\frac{i}{n})^2]

ocean sealBOT
mental prairie
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Sanks

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okay so now you're on your own to complete the question

muted raft
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You can simplify the series even more

molten rose
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yep, i got it

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I'm unable to do basic arithmetic in my current state of mind, I swear I'm not as clueless as I seem right now, I'm off to bed

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thanks for putting up with me though

muted raft
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you just need to take out 1/n^2 out and sum i^2 only

mental prairie
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yeah there's a reason for picking FM

mental prairie
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but sleep is what you need now

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Ciao man

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sleep tite

ocean patio
#

i have no idea on how to do this

glass lichen
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if they're the same shape then they're just translations of each other

ocean patio
#

so its still x^4?

glass lichen
#

yes

alpine sable
#

Hey could someone help out

craggy dirge
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how do you do c?

eager pebble
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I tried plugging in pi/4 but I just got 0/0 at the end

late tundra
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use lHospital's rule

late tundra
eager pebble
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wait of course

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thanks lol

tranquil pilot
#

hi everyone i got a question, someone can help me with a signal analysis with Fourier series?
its goes like this:
if f(x) = 4x, -1<x<3. Find:
the first 5 harmonics

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u guys know a book where i can find some info about how to find harmonics in those cases

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o the formula that is used to find that

alpine sable
mossy reef
#

So let's say I have a wheel and theres a 1% chance of winning after winning this 1% chance they spin another wheel and the outher wheel you have a 5% chance of winning 100,000$ what are the odds of winning the 100,000

late tundra
#

5%

wary stream
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No need to type in caps

lusty plaza
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google's first result explains it

quartz plinth
#

Hey guys

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I need help in Maths

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g(x)= 2/[2x+6] – 3

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This is the given x^

haughty dirge
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How do i find the length

minor dagger
#

<@&286206848099549185> can someone please help. me with these two

wary stream
minor dagger
#

you guys are aarguing ToT

minor dagger
lusty plaza
#

I would have such a hard time not banning people from this server if I was an admin

minor dagger
#

I read the info. and rules ToT

lusty plaza
#

yikes

round socket
#

OMG

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LMFAO WHAT THE HECK

lusty plaza
#

hopefully he catches a ban

alpine sable
#

<@&268886789983436800>

round socket
#

I JUST CAME HERE TO DO HW AND YALL BE HOMOPHOBIC?

alpine sable
#

musty is being racist, caught in 4k

sly mantle
#

👢

round socket
#

did he get banned

sly mantle
#

yes

round socket
#

anyone wanna help me with my hw doe

alpine sable
glass lichen
round socket
#

am i allowed to @ helpers for help

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i know

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i was just asking

glass lichen
#

after 15 mins like the rules say. . .

round socket
#

oh i dont read rules

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ok

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good idea

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brb!

glass lichen
#

then go do that

round socket
#

taking a ss RIGHT now

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BABY ITS THE BLACK BUISNESS

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ITS THE BLACK BUISNESS

minor dagger
#

what

round socket
#

WHEN YOU SEE US OUT HERE GETTIN GETTIN ITTT

#

JUST SUPPORT!

minor dagger
#

ToT

round socket
#

WOOO

#

SUPPORT

#

ok nvm i need help

minor dagger
#

this math is. due. really soon and. im so confused.

haughty dirge
#

the hell is going on

minor dagger
#

i. need help

round socket
#

I NEED HELP IS WHATS GOIN ON

minor dagger
#

with math

round socket
#

NAH ME FIRST

minor dagger
#

ive been waiting. before. you

proud burrow
#

@haughty dirge just subistute value of time in the given equation

minor dagger
#

patient

round socket
#

ASRAR HELP ME!

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@proud burrow !

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HELP!

wary stream
round socket
#

sorey

proud burrow
#

@round socket sorry but I am not good in geometry let me try

round socket
#

ok

alpine sable
proud burrow
#

@minor dagger you can send your question

round socket
#

um yes

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yes but no but yes

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if you know what i mean

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like

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yes but like

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not really no

alpine sable
#

Is it a test??

round socket
#

but like yes

#

no

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its old hw

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that was due MONTHS ago!

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best to do it asap!

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amiright????

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...

#

.....

#

....

round socket
#

NO ME FIRST

minor dagger
round socket
#

has it been 15 minutes yet

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should i spam them

wary stream
round socket
#

oh its only beeen 5 minutes

proud burrow
#

@round socket yeah just be patience

round socket
#

nvm

minor dagger
#

so 3(5+h)^2 is 3h^2+30h+7h buut how would i plug that in the slope equation to find the rate of change?

wary stream
late tundra
round socket
#

ugh everyone wanan help spaghetti but not me

#

like helo

#

OMG

#

ty

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i did it myself

minor dagger
#

...

round socket
#

i THOUGHT it was 115

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but i felt like

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it dindt make sense

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wait imma move to question-8 CHANNEL

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SOREY SPAGHETTI HAVE FUN!

quartz plinth
late tundra
minor dagger
#

thanks

alpine sable
# round socket

Ok so first join the centre of the circle T to P, R and Q. Now it's given that angle PTQ =130°.
Now look at the triangles PTR andd triangle RTQ.
PT=QT(Radio if the same circle)
TR=TR (common line segment)
PR=QR (common chord)
So angle PTR = Angle RTQ [CPCT]
Now take angle PTR as x. Here you go

quartz plinth
#

g(x)= 2/[2x+6] – 3 < given x

proud burrow
#

@minor dagger what's the question I am unable to understand can you explain me

minor dagger
#

so

#

i'll send it again

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@proud burrow can we go to a. different channel?

wary stream
#

Channel is occupied

minor dagger
#

oh thanks

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nvmd

quartz plinth
#

Aiii I’ll wait

proud burrow
#

@minor dagger what does net change means here I don't get that

minor dagger
#

i have. to find the net. change

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so thats

wary stream
minor dagger
#

i sibstitute the numbers into the equation then subtract it

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but how would i find the average. rate. of change like that

proud burrow
#

@minor dagger see change means you have to different you just can't subistute the number and subtract

minor dagger
#

i had to distrubite

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but for b

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the average. rate of change means i. use. the slope. formula

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how. can i do that if there is an h

proud burrow
#

@minor dagger like how you used slope formula

minor dagger
#

I'll try to see if it accepts the answer

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wait

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which would be y1 and. y2

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would y2 be the 5+h or the 3h^2+30h+75

proud burrow
#

wait you have understood wrong about net change and average rate of Change

minor dagger
#

oh..

proud burrow
#

Since f(z) = 3 - 4z^2

f(-2) = 3 - 4(-2)^2

= 3 -  4(4)

= 3 - 16

=-13

f(0) = 3 - 4(0)^2

= 3 - 4(0)

= 3 - 0

= 3

The net change is simply the difference f(0) - f(-2) = 3 - (-13) = 3 + 13 = 16

minor dagger
#

im only confused with. this one. because there is. letters

proud burrow
#

See this example you will understand what's the net change

minor dagger
#

yes, i know how. to solve it like thata

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but. i. dont know how. to. do it. withaletter. like

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5+h

proud burrow
#

So you got here confused

minor dagger
#

yes

proud burrow
#

@minor dagger wait let me try if I can find it out

minor dagger
maiden carbon
#

Oh wait is this still in use?

proud burrow
#

@minor dagger I think we can't eliminate h

minor dagger
proud burrow
#

Because we don't know what is h or what's the function of h or anything about h

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@minor dagger I Thik you told before like using slope before you told

minor dagger
#

i. was able to. figure it out

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for slope

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3(h+10)

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but i cant for net. change @proud burrow

#

can you help me with. that one?

proud burrow
#

@minor dagger sorry but the question you have asked is actually a new concept for me and confusing to me sorry to say but I can't help you

minor dagger
#

its okay, thank you. though!

proud burrow
#

Yes out t= 20 in your given equation and then solve for length

#

*put

acoustic reef
#

This chat being used?

late tundra
#

nope

acoustic reef
#

Does that look right?

#

Verifying Identity’s

late tundra
#

yes they r all correct

acoustic reef
#

🙂

#

Thanks!

ivory zodiac
#

guys this question is physically impossible, right?

#

cause Fa would have to be greater than 245 N

ionic jewel
#

that doesnt sound right

ivory zodiac
#

but if it's the minimum, which is 245 N, the acceleration is 5.3 or smt like that

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and anything less than that, the system will move the other direction

ionic jewel
#

no

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theres no reason you couldnt accelerate it at 0.3 m/ss

ivory zodiac
#

how would that work??

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because the friction on the table is 45 N

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and the m2 weight is 200 N

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so to make it move in the direction of M1, you need to overcome 245 N

proud burrow
#

You should also add the foce due to hanging block with friction because they are in same direction

ivory zodiac
#

the hanging block doesn't have friction tho

proud burrow
#

I am not telling to add friction I am telling to add forces

ivory zodiac
#

yes

#

200N + 45 N

pure hill
#

I don't see anything impossible, yeah its true that the force should be greater than 245N

ivory zodiac
#

right, but anything greater than 245 ends up giving a number larger than 0.3m/ss

pure hill
#

but acc to me the answer should be 252.5N

ivory zodiac
#

i think i got taht answer too

#

but when i verified it

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A ended up being 5.3 smt

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(m1+m2)a = Fnet

ionic jewel
#

the verification is wrong

pure hill
ivory zodiac
#

pls do tell

ionic jewel
#

you didnt account for friction then

pure hill
#

just a sec let me do a bit more calculation

ivory zodiac
#

Fnet counts the friction in

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shoudl it not

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cuz

ionic jewel
ivory zodiac
#

hold on a sec

ionic jewel
#

but again i havent done physics in a while but its definitely possible to do

pure hill
#

can you please tell what the answer is because i am getting 258.5N

proud burrow
#

@pure hill how did you find fnet

pure hill
#

see first I found the force due to the hanging block and due to the friction on the block that is placed on the table that was fnet

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and then to find the force

pure hill
#

but in place of fnet

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I put F

ivory zodiac
pure hill
#

and then I added F and fnet

ivory zodiac
#

even if u account for the friction

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(which i don't rlly think u should cuz it should be included but i could be totally wrong)

#

u get 4.6111

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i think its cuz

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u need a certain acceleration to even overcome the weight and the friction

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and 0.3 m/ss is simply not big enough

pure hill
#

I just am asking that do you know the correct answer?

ivory zodiac
#

nope

#

this was a quiz given my a physics teacher who makes tons of mistakes and my class and i r losing our minds

#

so our concensus is he just made a mistake

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but i dropped by here just to make sure

pure hill
#

you don't need that acceleration you want a particular force that is going to overcome all the opposing forces and then provide extra 0.3 m/ss acceleration

ivory zodiac
#

yes

#

but all the answers we get

#

we r tryna verifyu

pure hill
#

so its totally possible

ivory zodiac
#

to see if we get the correct acceleration

#

and its just not working

pure hill
#

see verification in this type of questions is a bit tricky

ivory zodiac
#

ah wells its fine thank yall for the help i must go sleep i am spent

pure hill
#

when you do verify you need not just put (m1+m2)a = fnet where you are takng fnet = 245N no thats totally wrong

ivory zodiac
#

ur help was very much appreciated bunny and asrar and darklord

#

but it cannot be anyyyy less than 245 n

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so if i were to put 245 n, i expect an answer less than or equal to 0.3 m/ss

#

but its fine im tired

pure hill
#

you are not getting it you don't have to verify

pure hill
proud burrow
#

There's no conditions given so it may be more or less than 245

ivory zodiac
#

yee tyvm

ocean sealBOT
#

xHardcorexism

#

xHardcorexism

calm kiln
#

This free?

candid minnow
#

how do you find the relative displacement given 2 points in a 2d coordinate system

torpid narwhal
#

hi i'm trying to get the sum of all even numbers from 0 to 2n, for any positive integer n

#

so i have

Sigma (i=0 to n) 2i = 0 + 2 + 4 + ... + 2n
= 2n + Sigma(i=0 to n-1)
= 2n + 2(n-1) + Sigma...

torpid narwhal
#

= 2n + 2(n-1) + 2(n-2) + ... + 2 + 0

vagrant cobalt
#

Maybe n(n+1) for your case

torpid narwhal
#

= 2n + 2n - 2 + 2n -4 +... + 4 + 2+ 0

#

and if you cancel the constants out

#

dont you get 2n

#

?

vagrant cobalt
#

Take 2 common

torpid narwhal
#

hm?

vagrant cobalt
#

2 common from each term

#

You end up with 2 times

#

Sum of integers from 1 to n

torpid narwhal
#

oh wait so

#

i get to
(2n - 0) + (2n - 2 ) + (2n - 4) + ... + 4 + 2 + 0

little wadi
#

my bad

glossy tendon
#

Sum of Integers from 1 to n is $S_n = \frac{n(n+1)}{2} = 1+2+3+...+n$
Multiply it by two $2S_n = 2\frac{n(n+1)}{2} = 2(1+2+3+...+n) = 2+4+6+...+2n$

ocean sealBOT
torpid narwhal
#

that's not helpful

arctic dirge
#

Please help me in this question

alpine sable
#

Is $x^{1}-x^{-1}=/frac{x^{2}-1}{x}$?

#

,w x^{1}-x^{-1}=x^{2}-1

#

,w x^{1}-x^{-1}

arctic dirge
#

thanks

lofty compass
#

Algebraic vectors

alpine sable
#

3+(-2)+(-1)=0

lofty compass
alpine sable
#

I really don't know. I don't think it's something to do with that.

nocturne flint
#

x²- x⁴

lofty compass
#

Don’t know how to do the first part

alpine sable
ocean sealBOT
#

Ranok Hui

alpine sable
#

Andrea is opening a gourmet donut shop. The fixed monthly costs (rent, insurance, electricity, etc.) will be $18,000. It costs $0.25 to produce each donut.

Write a function c(x) to represent the cost of business based on x number of donuts product

#

can i do

#

c(x) = 18,000(1.25*x)

#

I interpreted 3 -2 -1 in, and got 3

#

oh ok

#

nice

oak matrix
alpine sable
#

oh yea

#

c(x) = 18,000+1.25*x

#

like tha

#

right

oak matrix
#

0.25 x

#

c(x)=18000+0.25x

alpine sable
#

ok

#

thx

#

love ya

#

<3

#

love ya a lot

#

@oak matrix

oak matrix
#

Btw can anyone help with one

alpine sable
#

<34333

oak matrix
oak matrix
alpine sable
#

I guess?

#

I'll try some other numbers

tranquil tulip
alpine sable
#

x=2
y=-1.5
z=-0.5

oak matrix
nocturne flint
#

Check that p(X) is a multiple of g (X) or not p(x)=X³ - 5X² + 4X - 3 g(x)= -7

#

can someone help

alpine sable
#

I got 3 again?

alpine sable
#

Idk negative factorials...

#

I can't help

#

,w \frac{4!}{(4-15)!15!)}

#

0

remote shard
#

can someone help me real quick

alpine sable
#

Sure

remote shard
#

I need the formula of a revolution around a certain x axis

#

how do I tweak the formula

#

so the integration formula and then i need to find the volume around line x=4

#

how do i change that

alpine sable
#

Oh no, I don't know integrals

alpine sable
#

How do I find tan, csc, or sec in unit circle

shrewd sable
#

All of those can be derived from sin and cos

oak chasm
#

@alpine sable They switched the numbers by accident.

#

Should have been 15C4.

alpine sable
#

Is sec reciprocal or cos ?

oak chasm
#

It is.

#

csc is reciprocal of sin

#

tan is sin/cos

#

cot is cos/sin

#

So, just get sin and cos from the unit circle, then use those.

alpine sable
#

Oh damn I completely forgot that’s how it works

ocean sealBOT
#

Chai T. Rex

alpine sable
oak chasm
#

Right.

#

sec = 1/cos, so yes.

alpine sable
#

And what abt -1?

oak chasm
#

For the secant?

alpine sable
#

Yeah

oak chasm
#

So, take the reciprocal of -1 to get the cosine.

alpine sable
#

Ima says -1/2?

oak chasm
#

That's not the reciprocal of -1.

ocean sealBOT
#

Chai T. Rex

oak chasm
#

What does that become?

alpine sable
#

Stays -1

oak chasm
#

Right.

#

So, if secant is -1, cosine is also -1.

alpine sable
#

So for reciprocal it will always have 1 on top and the we use under it ?

oak chasm
#

Yep.

#

Or flip a fraction if you have one of those.

#

So, if the secant is 2/3, the cosine is 3/2.

#

If the secant is -4/5, the cosine is -5/4

#

But for nonfractions, yes, 1 over the number.

alpine sable
#

Can you help me solve this one

#

Idk what to do after getting 2.11

oak chasm
#

What is the question asking?

alpine sable
oak chasm
#

Oh, OK.

#

,w acos(-0.51)

ocean sealBOT
oak chasm
#

@subtle oasis Sorry, channel is busy.

#

@alpine sable Cosine is the x value, right?

alpine sable
#

Yeah

oak chasm
#

OK, draw a unit circle.

alpine sable
#

Yeah I got one on my screen rn

oak chasm
#

Then, draw the line where x = -0.51.

#

It'll be a vertical line that touches the circle at two points, right?

alpine sable
#

Yeah since it’s cos

oak chasm
#

OK, so you have two angles that touch the circle at those points, right?

#

You have one angle. How do you get the other?

alpine sable
#

It’s across from it but hold on I’m kinda having trouble getting to -.51 on the unit circle

azure yew
#

9 + 10 =

oak chasm
#

@azure yew Sorry, channel is busy.

alpine sable
#

It would be at around like 2pi/3 right ?

oak chasm
#

That's one angle.

#

How do you get the other?

alpine sable
#

4pi/3

oak chasm
#

No.

#

That's a number, not a "how".

alpine sable
#

Drawing a straight vertical line down

#

To line up with the other fraction

oak chasm
#

No, here's how you do it.

#

Start at angle pi.

#

Go clockwise to get the first angle, right?

alpine sable
#

5pi/6 is the next one right

oak chasm
#

No.

#

Start at angle pi.

#

You can go clockwise to get the first angle, right?

alpine sable
#

By angle pi you mean (-1,0) right

oak chasm
#

Yes.

#

That's where angle pi hits the circle.

#

And you can go clockwise to get to the first angle, right?

alpine sable
#

Pi/2?

oak chasm
#

Stop with the numbers please.

#

Please answer the questions.

alpine sable
#

Yh i see the next angle

#

While going clock wise one angle

oak chasm
#

Do you see that it's clockwise from pi?

#

OK.

#

How far clockwise from pi?

alpine sable
#

30 degrees

oak chasm
#

No.

#

How do you find how far clockwise an angle is from pi?

alpine sable
#

By checking the degrees ?

oak chasm
#

No.

#

We're working with radians.

#

Stop working with degrees, please.

alpine sable
#

Oh the pi fractions

oak chasm
#

No.

#

No fractions.

alpine sable
#

Then I’m not too sure

oak chasm
#

Did you get a fraction of pi for the first angle?

alpine sable
#

Ok so ima clarify something you wanted me to start at pi right ? After that go clock wise one angle right ?

oak chasm
alpine sable
#

This one

oak chasm
#

No!

#

What angle did you get?

alpine sable
#

I don’t know how to do this well that’s why I’m terrible at it

oak chasm
#

You got 2.11, right?

alpine sable
#

Yeah

oak chasm
#

You didn't get a fraction of pi, you got 2.11.

#

Please stop with the fractions of pi, since we're not dealing with those.

#

So, how many radians is that clockwise from pi?

alpine sable
#

1.03

oak chasm
#

Right!

#

Now the other angle is that counterclockwise from pi.

#

What angle is 1.03 radians counterclockwise from pi?

alpine sable
oak chasm
#

@alpine sable Sorry, channel is now busy.

alpine sable
oak chasm
#

@alpine sable The angle increases as you go counterclockwise, right?

alpine sable
#

Yeah

oak chasm
#

So, what's pi + 1.03?

alpine sable
#

4.17

oak chasm
#

Right.

#

Which answer has 2.11 and 4.17 or nearby?

alpine sable
#

Answer D

oak chasm
#

Right.

#

Do you want to do another problem?

alpine sable
#

Yeah I have one for tan

oak chasm
#

OK.

alpine sable
oak chasm
#

@alpine sable One second. Last problem, we had this:

#

The top angle is just as far from pi as the bottom angle.

#

Does that make sense?

alpine sable
#

Yeah

oak chasm
#

OK, so you find out how far the first angle is from pi.

#

pi - 2.11.

#

That's 1.03.

#

Then the second angle is that far from pi.

#

pi + 1.03.

#

4.17

#

Does that make sense?

alpine sable
#

Oh yeah that makes it seem a lot simpler than I originally imagined

oak chasm
#

Yeah, you got confused into thinking it was a fraction of pi because I said to look at the unit circle, I think.

alpine sable
#

It’s because I didn’t know we could describe angles in radians

oak chasm
#

Oh, OK.

alpine sable
#

I’ve never done that I always used degrees, and fractions but now I got it

oak chasm
alpine sable
#

Alright

oak chasm
#

Now, here's a trick with tangent.

#

It gives a slope.

alpine sable
#

Dang

oak chasm
#

So, the tangent gives a slope of 3.3.

#

So remember that for later.

alpine sable
#

Ok

oak chasm
#

What angle has tangent 3.3?

alpine sable
#

Well wouldn’t we to arctan (3.3) ?

oak chasm
#

,calc atan(3.3)

ocean sealBOT
#

Result:

1.2765617616837
alpine sable
#

And then go on from there

oak chasm
#

Right, so that angle.

alpine sable
#

Oh ok

oak chasm
#

Now let's think about this.

#

We have a line with a slope.

alpine sable
#

Yeah

oak chasm
#

,w plot 3.3x

ocean sealBOT
alpine sable
#

So it’s going to go diagonal

oak chasm
#

Right, like the graph above.

alpine sable
#

Yeah

oak chasm
#

So, see the upper right section?

#

That goes up and right from (0, 0)?

alpine sable
#

Yeah first quadrant

oak chasm
#

OK, now what happens if we start at that angle and add half a revolution to it?

alpine sable
#

It will be in quadrant 3 where the other half is

oak chasm
#

Right.

#

We get exactly the opposite angle going at the same slope the other way, right?

alpine sable
#

Sure

oak chasm
#

OK, so how many radians is half a revolution?

alpine sable
#

You want me to answer with numbers or pi

#

3.14 right ?

oak chasm
#

Either one.

#

Right.

#

So, if you have an angle, that angle plus pi will give the same tangent.

alpine sable
#

Oh ok so there’s 2 pi or 7.28 radians per circle, I didn’t know that

oak chasm
#

Because it makes the same slope.

#

Does that make sense?

alpine sable
#

Yeah

oak chasm
#

OK, you can also subtract pi.

#

You can add or subtract as many half revolutions as you want and you'll end up with the same slope.

#

So, we have:

#

,calc atan(3.3)

ocean sealBOT
#

Result:

1.2765617616837
oak chasm
#

Add a half revolution.

alpine sable
#

4.41

oak chasm
#

Right, so which answer?

alpine sable
#

Adding pi to 1.27

#

D

oak chasm
#

Right.

alpine sable
#

Oh ok got it

maiden carbon
#

I was thinking to assume RVT was 90 total since it looks like it but it has no marking so im confused

oak chasm
#

No, don't assume.

maiden carbon
#

I need RS to be able to use trig on it

#

since then ill have all 3 sides

#

but I dont and thats what im trying to find

#

so this is a pre-trig problem (maybe?)

ocean sealBOT
#

Chai T. Rex

maiden carbon
#

yes

#

i still cant use trig since i need 2 sides though

#

or am i thinking about this wrong

#

oh lmao wait i can use other triangle

ocean sealBOT
#

Chai T. Rex

oak chasm
#

Top line is for left triangle. Bottom line is for bottom triangle.

maiden carbon
#

I was gonna do cos(6/12)

#

and get S

#

then subtract S from 180

#

and do the a/A = b/B for the rest

oak chasm
#

You don't know that it's a right triangle.

maiden carbon
#

oh right yeah i forgot

#

this is a review test for the whole year so yeah

oak chasm
#

Law of sines works for any triangle.

#

So, use it for the left and right, as I did above.

maiden carbon
#

I am confuse

quasi pulsar
ocean sealBOT
#

Chai T. Rex

oak chasm
#

@quasi pulsar Sorry, channel is busy.

quasi pulsar
#

it’s ok

maiden carbon
#

Yeah i know law of sines i kinda forgot how to use it, it was a few units ago

#

all i remember is

#

a/sinA = b/sinB = c/sinC

#

the issue is that i need more than one side for that to work right?

oak chasm
#

What?

maiden carbon
#

hm?

#

I only have RV

oak chasm
#

No, you have a/sin(A) = b/sin(B) = c/sin(C).

#

Right?

maiden carbon
#

Right

oak chasm
#

So, you have everything as variables and it's still true, right?

maiden carbon
#

yeah

#

im just trying to figure out how that works

oak chasm
maiden carbon
#

yes i see the equation, why does it work for this problem though

oak chasm
#

No, read it.

#

Don't see it.

#

Read it.

maiden carbon
#

the issue im facing with understanding it is that afaik you need atleast all 3 sides of a triangle, or an angle and the opposite side

oak chasm
#

No.

#

Do you see how I got the second two equations?

maiden carbon
#

Well i dont know how you got them but i understand that RSV + VST is 180

#

the issue is that i dont know what they are split apart

#

I just know the sum

oak chasm
#

Right, you don't need to.

#

You keep trying to figure out irrelevant things.

#

Of course you can't find that, so that's obviously not the way to solve this since you can't do that.

#

When you can't do something, it's generally not the way forward.

maiden carbon
#

i dont know why this is relevant, i dont understand the equasion

#

or why it works

oak chasm
#

OK, you know law of sines, right?

maiden carbon
#

yes

peak niche
#

a/SinA =b/SinB = c/SinC ^

maiden carbon
#

yeah but as far as i know you need atleast multiple values for that

peak niche
#

Yea you need 2 sides and an angle or 2 angles and a side

ocean sealBOT
#

Chai T. Rex

oak chasm
#

From the left triangle.

maiden carbon
#

but this wouldnt be solvable unless i had either RVS or RS right?

oak chasm
#

Stop with that.

#

You know some methods of solving it.

#

They aren't working for you, right?

maiden carbon
#

yeah

oak chasm
#

So maybe stop thinking you should use them.

#

For your methods, you need to have either of those.

#

For mine, no.

#

We're not using your methods, so we don't need the requirements of your methods.

peak niche
#

Give the angle an X value and solve by equation?

maiden carbon
#

AH i was confused i thought you wanted me to solve the first equasion

peak niche
#

Just an idea

maiden carbon
#

second equasion is the one thats actually solvable

#

since it has atleast one variable on each side

oak chasm
#

No, it isn't.

maiden carbon
#

wait it isnt?

oak chasm
#

Neither one is solvable.

#

We just want the equations for now.

#

Then, in the bottom two equations, we fill in things that are equivalent.

maiden carbon
#

why is the first equasion on the bottom there

#

i dont get how TVS/RS is equal to RSV/8

oak chasm
#

Law of sines.

maiden carbon
#

or are you interpreting all the triangles as one

#

instead of two

oak chasm
#

LAW OF SINES

peak niche
#

Find the other angles in terms of x

oak chasm
#

No.

maiden carbon
#

yes i know law of sines but its a different triangle

peak niche
#

Then make it = 180

oak chasm
#

One equation is for the left triangle.

#

@peak niche No.

peak niche
#

Awh

#

Ok

oak chasm
#

One equation is for the right triangle.

maiden carbon
oak chasm
#

Do you see that one is for the left and one is for the right?

maiden carbon
#

Am confused by this

#

because its a different triangle for each

oak chasm
#

No!

maiden carbon
#

not the same one

oak chasm
#

Do you see that that's for the left triangle?

#

Both angles are in the left triangle, right?

#

Both sides are in the left triangle, right?

maiden carbon
#

oh right

oak chasm
#

Oh, I see.

#

You see that $\angle TVS$ is in the right triangle.

ocean sealBOT
#

Chai T. Rex

oak chasm
#

Look at the top two equations.

maiden carbon
#

yeah i saw now

oak chasm
#

They're for the left and right trinagles.

maiden carbon
#

the angle is the same for both

oak chasm
#

Right.

#

I replaced one with the other.

#

Then I replaced one angle with 180 degrees minus its supplementary angle.

#

Does it make more sense now?

maiden carbon
#

yeah

#

on the last equsion why do you do 180-

#

if you are already solving for half

#

if you are using RSV

oak chasm
#

See how I get these from the second two equations?

#

Bah.

ocean sealBOT
#

Chai T. Rex

oak chasm
#

See how I got these two equations?

maiden carbon
#

... no

#

i remember that you can put something in front of the sin but i forgot what it does

oak chasm
#

This is algebra.

#

This isn't your trigonometry knowledge.

maiden carbon
#

im just a bit confused because why would it be sin(180-RSV) and not just sin(RSV)

oak chasm
maiden carbon
#

yeah RSV+VST = 180 but if you are doing sin(RSV)/8 it should solve for RSV

oak chasm
#

What are you talking about?

#

The 180 minus is in the other equation!

maiden carbon
#

what

oak chasm
#

You're talking about something over 8.

maiden carbon
#

im talking about this

oak chasm
#

That's in the TOP equation.

#

Do you see an 8 in that?

maiden carbon
#

oh wait

#

ok now im confused

#

you have 180-RSV in there, but you have it over 12

oak chasm
#

Right.

maiden carbon
#

if you wanted to solve for 12 i would assume you do VRT

oak chasm
#

What does solving for 12 even mean?

#

12 = 12.

maiden carbon
#

i mean

oak chasm
#

It's already solved.

maiden carbon
#

sin(VRT)/12

oak chasm
#

VRT?

#

Where do you see that anywhere?

maiden carbon
#

ok so holdup 180-RSV is VST and sin(VST)/12 is essentially the same thing as what you put

oak chasm
#

Right.

maiden carbon
#

but then why put 180-RSV

oak chasm
#

Because it's equal to what was there before.

#

So we can replace it.

maiden carbon
#

ah

gilded cipher
#

hey

#

can anyone help me with a question

oak chasm
#

@gilded cipher Sorry, channel is busy.

gilded cipher
maiden carbon
#

im guessing i cant solve the last equation yet either

oak chasm
#

No.

oak chasm
maiden carbon
#

yes, you put the denominator from one side and cross it to the other

oak chasm
#

Right.

ocean sealBOT
#

Chai T. Rex

oak chasm
#

Do you see how I got that?

maiden carbon
#

uhh

#

where did RS come from it wasnt in the old equation

oak chasm
maiden carbon
#

yes i see them, dont understand them anymore

oak chasm
#

OK.

maiden carbon
#

idk where RS came from

oak chasm
#

I was explaining that.

#

But you can't understand the last step.

#

If you forget what's happened, it's really hard to make progress.

#

Since every step is based on previous steps.

peak niche
#

If in doubt guess 9 that's my motto

oak chasm
#

@leaden ferry Sorry, channel is busy.

maiden carbon
#

you combined the last 2 steps and i dont get it

oak chasm
#

Do you get the previous steps?

leaden ferry
#

Ah, of course. I'll just repost it on the other channels that is not active...

maiden carbon
#

yeah i understand the very last step of the other image

oak chasm
#

OK, do you see that both left sides are the same?