#help-0

1 messages · Page 850 of 1

marble saffron
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hey so to go back on this

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is the square root of x^2 always -x when aproaching

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-infinity

alpine sable
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I have to come up with sizes of the prism

marble saffron
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or any negative value?

alpine sable
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I dont have an image

dusky rain
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i dont think it can then

alpine sable
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Leme translate it from dutch

tidal bane
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How does one hypothesis test?

alpine sable
#

Can i dm you the text?

dusky rain
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alright

coral wren
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i asked the teacher if we could do some system of equations, instead of doing random equations we did last year, and she said, later and then we never did the m 😂

tidal bane
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specifically to find the alpha value associated with p1 =/= p2

quasi lodge
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anyone can help me with the chapter circles gade 8

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grade 8*

coral wren
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what do you need?

alpine sable
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i need help with polynomial functions and real roots

quasi lodge
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do u know about OO prime and RR prime?

coral wren
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i suppose maybe someone else can help, i am in 8th aswell

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is that the final answer?

dusky rain
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no

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im actually not too sure about that question

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are you supposed to answer it in terms of a or in terms of a number

alpine sable
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does anybody know? <@&286206848099549185>

dusky rain
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im pretty sure it doesnt work in terms of a number

coral wren
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then it has to be a letter

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which is fine

dusky rain
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yea

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its just 5a+6

coral wren
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so thats the final answer?

dusky rain
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i guess yeah

coral wren
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to me it seems fine

ivory gulch
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alr u guys done

coral wren
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what

ivory gulch
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don't want to interrupt

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🙂

dusky rain
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its ok lol

coral wren
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anyone can ask whenever

ivory gulch
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ok sick

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here's what i've got

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so i picked a = 256 bc its a 4th root

alpine sable
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@tough tangle

crisp grove
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f(x) =x^¼ @ivory gulch , x0=256

ivory gulch
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$L\left(x\right)=f\left(a\right)+f'\left(a\right)\left(x-a\right)$

ocean sealBOT
ivory gulch
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and when i sub everything in i get L(x) = -12 + 1/16 x

tough tangle
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one of the last 2

ivory gulch
crisp grove
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-12?

ivory gulch
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do i plug 264 back in

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f(a) = 4, f'(a) = 1/16, a=256

crisp grove
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$f(x+\delta x) = f(x) + f'(x)\delta x$

ocean sealBOT
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Ryuzaki

crisp grove
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yr x is 256 and dx=-1

ivory gulch
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$L\left(x\right)=4+\frac{1}{16}\left(x-256\right)$

ocean sealBOT
crisp grove
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🤨

ivory gulch
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this is the equation for linearization no?

crisp grove
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think it is

ivory gulch
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alr so

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if i plug everything i get

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$L\left(x\right)=4+\frac{1}{16}x-\frac{256}{16}or:16$

ocean sealBOT
ivory gulch
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or x/16 - 12

alpine sable
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4+1/32

ivory gulch
crisp grove
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yeah

tough tangle
crisp grove
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then sub in 254, what's the issue?

ivory gulch
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u mean 264?

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or

crisp grove
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yeah 264

ivory gulch
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bc it's wrong

ivory gulch
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answer is 129/32 according to the key

crisp grove
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,w derivative of x^(1/4) at x=256

coral wren
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How do i know where to put the x=

ivory gulch
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jesus \

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this chat is chaos rn

coral wren
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yes

crisp grove
ivory gulch
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,w derivative of x^1/4

ivory gulch
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oh forgot to cube

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sad day

alpine sable
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It's correct

crisp grove
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i trusted u that u had calculated the deriv correctly

karmic rapids
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Have you done here?

ivory gulch
crisp grove
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@karmic rapids there are 9 different channels to ask

ivory gulch
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i forgot to cube

quasi lodge
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,w 2+2

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so hard!!

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,w 2787823789283+7828738278274

alpine sable
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How do i calculate the area of an cone again?

edgy sand
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how is D wrong?

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i feel like im just messing up the notation somehow

bold quail
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greater then or equal to

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0

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right?

alpine sable
edgy sand
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it wants interval notation

alpine sable
bold quail
edgy sand
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it says wrong

alpine sable
alpine sable
edgy sand
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i think it wants it with that U symbol

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how would it look like with that?

alpine sable
edgy sand
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i found the slope of the function for position

silver current
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Take lcm for the LHS

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after making both LHS and RHS in one term each, cross multiply

pine cipher
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anyone?

slow swift
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For every 5 pizzas increased, the price is increased by roughly 26

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The plus c should always be the "initial cost"

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Because when you sub in 0 for x you should be left with just c for example like in questions where height of a thrown object is modeled

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Not sure if ur meant to take the price for 5 pizzas as initial though

alpine sable
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I have to sum every 3 digit number that can be formed with 1, 5, 6, 7, 8 and 9, and those digits can't be repeated

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So we have 120 different numbers

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And I don't know how to start calculating this sum... I don't find any clue... or just anything

placid zinc
peak iron
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Hi, how can this be done?

placid zinc
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I might not be familiar with the notation. Does the x² + x + 1 part mean that x satisfies x² + x + 1 = 0?

peak iron
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It is like Z2, Z3, Z4,... with modulos

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But instead of modulo a number, it's the 'modulo' of a polynomial

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It's a field

placid zinc
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Right, I understand what Z2[x][y] would be

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But that x² + x + 1 bit in the middle is something I haven't seen before

peak iron
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What would Z2[x][y] mean?

sick torrent
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How do you do a question like this?

alpine sable
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@past sleet @alpine sable So I already proved it for n =1 , n = 2

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But im confused at this part

past sleet
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Now what we want to do is assume it is true for any n, and then show that that implies it holds for n+1

alpine sable
past sleet
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well ur gonna wanna do this one sec

alpine sable
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Like if were proving for n + 1 wtf is K

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n is just K i dont understand why we switched notation lol

past sleet
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ah, these are dummy variables dont pay too much mind to it

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basically the idea with induction is

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prove that you can get onto a rung on a ladder (prove a base case), and then prove that you can get from one rung to another (inductive step). So you can conclude then you can climb the whole ladder

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does that make sense

alpine sable
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Yeah that makes sense to me

past sleet
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Right so you've shown you can get onto a rung on a ladder

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now we just need to do the inductive step

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So consider for any natural number k

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$\sum_{i=1}^k i = \frac{(k)(k+1)}{2}$

ocean sealBOT
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mirzathecutiepie

past sleet
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Now we need to show $\sum_{i=1}^{k+1} i= \frac{(k+1)((k+1)+1)}{2} = \frac{(k+1)(k+2)}{2}$

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r u with me

alpine sable
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umm one sec

ocean sealBOT
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mirzathecutiepie

alpine sable
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so we are just kinda factoring out the terms of k rn right

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K + 1

past sleet
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we are just setting up the problem rn

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like what are we starting with, what do we want to prove

alpine sable
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Oh ok so, if I remember corecty you just have to show that this will work for K + 1 and then it will imply it works for any K + infinity. So we only need to prove the K + 1 case? Or do we still have to prove just K also

past sleet
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No we assume its true for any K, then we show it's true for K+1. We need to show we can get from one ladder to another

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one sec let me give u some intuition for this

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suppose we have a proposition P, some property relating to the natural numbers. Now suppose we start with P(1) being true. Suppose we've proven this. And suppose also that P(k) => P(k+1)

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Now let's say i want to know if P(4) is true

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well I know that P(1) is true, and P(1) => P(2) is true, and P(2) => P(3) is true and P(3) => P(4) is true

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So we get this chain of implications

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Suppose i want to know if P(10) is true

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P(1)=>P(2)=>P(3)=>P(4)=>....=>P(9) =>P(10)

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so this can be done for any natural number

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So this is what we want to do

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does that make sense hmmCat

alpine sable
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Yeah so instead of => we just want to see if this specific formula holds true for K + 1?

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which is represented by P

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lmao

past sleet
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No when we're doing P(k) => P(k+1) we're setting up this way to climb the ladder per se

alpine sable
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ok ok

past sleet
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If we show P(1) is true and P(k) implies P(k+1) then P(2), P(3),P(4),P(5),.... all are known to be true

alpine sable
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I think I get it were just assuming K is true , and setting up K + 1, we havnt solved anything yet

past sleet
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yeah precisely

past sleet
ocean sealBOT
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mirzathecutiepie

ripe rock
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Hello quick question, how do you do c^d mod n for large numbers on the TI calculator Nspire for RSA method

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currently giving me this

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but answer is 2021

past sleet
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idk hun i think it'd be better if u asked in a diff channel

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we're busy rn

past sleet
alpine sable
past sleet
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remember because $\sum_{i=1}^k i = 1 + 2 + 3 + ... + k$

ocean sealBOT
#

mirzathecutiepie

alpine sable
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Right so for i = 1 is just K + 1 + 1

past sleet
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$\sum_{i=1}^{k+1} i = 1 + 2 + 3 + ... + k + (k+1)$

ocean sealBOT
#

mirzathecutiepie

past sleet
alpine sable
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ohh

hybrid flower
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If i have 10% chance for event to happen, and i roll 4 times, what is the chance for the event to happen twice?

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Kind of noob question lol

alpine sable
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So you sum untill K + 1 , increasing by K times to K + 1

past sleet
ocean sealBOT
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mirzathecutiepie

past sleet
alpine sable
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Yes that makes sense

past sleet
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i = 1 and then you evaluate the expression after the sum sign, then i = 2 and you evaluate the expression after the sum sign, and you add these two together, and so on

past sleet
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keep in mind the expression we want to reach

past sleet
alpine sable
past sleet
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gud

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ping me when ur done btw

alpine sable
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just to be clear I'm supposed to get

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from this process

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@past sleet

past sleet
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yeah

alpine sable
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Ok I think I am a cringe poser in the math community lmao

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I got some wack answer

past sleet
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Sure go for it

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it's how we learn

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plus don't be worried about being cringe and stuff there's always someone out there who'll find you cringe for something, best not to worry about it

alpine sable
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Well If I remember my fractions, you cant just add a fraction with a different denominator, so I multiplied (k + 1 ) by 2 so I could add it to K(K+1)/2.

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Is that even close to what I should be doing lmao

past sleet
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perfect

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great job

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yes that's precisely it

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$\frac{k(k+1) + 2(k+1)}{2}$

ocean sealBOT
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mirzathecutiepie

past sleet
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now just one step left

alpine sable
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Right, thanks! Then I cant remember... you could just reduce 2/2 so it would be just k(k + 1) + (k + 1)? I cant remember if thats allowed because 2 is part of the (k+1) term

past sleet
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no that's not allowed

alpine sable
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dangit i always try doing that lmao

past sleet
gloomy wharf
alpine sable
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Okay ill do it without randomly canceling the 2

past sleet
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$(\frac{1}{2})(k(k+1)+2(k+1)}$ so "cancelling out" is just applying distributive property ukwim

ocean sealBOT
#

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

vague coral
gloomy wharf
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give answer pls

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thx

vague coral
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do it yourself

gloomy wharf
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...

past sleet
gloomy wharf
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y=11x?

vague coral
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I don't know, I didn't calculate

alpine sable
past sleet
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How do you get from $\frac{k(k+1)+2(k+1)}{2}$ to $\frac{(k+2)(k+1)}{2}$

ocean sealBOT
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mirzathecutiepie

alpine sable
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So my thinking is that the k from the first term and 2 creates the (k + 2) , and that some how one of the (k + 1) terms is canceled... I know multiplying the numerator out is not the answer cause you'd end up with a quadratic equation of k^2 + 3k + 2. So my next thought was to multiply by 1. I tried multiplying the whole equation by (k + 1 ) and (k -1 ). That did not seem to work either 😅 I feel like that should have been the method though maybe I chose the wrong number to multiply by lol

past sleet
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you were right at first

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Notice thatwe have

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$a(b+c) = ab +ac$

ocean sealBOT
#

mirzathecutiepie

past sleet
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so basically we can pull out the (k+1),

past sleet
#

in fact both answers work

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you can multiply out the numerators in both and show that they are equal

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or, you can factor out the k+1 and make it (k+2)(k+1)

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to drive this further home

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(k+1)(k+2) = (k+1) * k + (k+1) * 2

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= k(k+1) + 2(k+1)

alpine sable
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Ohh I didn't know if you could just pull it out of the two terms like that, my math fundamentals are so bad

past sleet
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ah it's nothing

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we were all there

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i recommend having a look at khanacademy or paul's online notes. Try to understand why the rules are the way they are and stuff will start to click nicely catthumbsup

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I hope that helped tho

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so we've completed the inductive step

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and so the proof is complete!

alpine sable
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Yesss I'll have to check that out, I use KA for linear algebra rn 😅 . Thank you! You made alot more sense than the book

past sleet
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that's no issue

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shoot me a dm or ping me if u need further help : )

alpine sable
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Thank you! Ill be writing this out now formally and make sure it makes sense to me

past sleet
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sure no problem, ping me if u get stuck or need clarification

proud kestrel
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How can I show that the magnitude of H is dependent on KA but the angle isn't?

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I mean it makes sense if I think about it graphically like a vector, multiplying by a scalar doesn't change direction

alpine sable
proud kestrel
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Control systems :p

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Should I consider each factor as a complex exponential?

toxic meadow
#

can someone please guide me through this

alpine sable
pale pond
#

anyone know what "Log-temporal delay" means?

glass lichen
pale pond
#

ya don't see anything for that exact wording, main stuff that comes up is on "Logarithmic based optical delay", which might be what its referring to

buoyant kayak
toxic meadow
buoyant kayak
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right, and where does your graph go through the x axis?

toxic meadow
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(0,0)

buoyant kayak
#

so which coordinate changes?

toxic meadow
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x

buoyant kayak
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and do you know how to represent a translation in x?

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in the function ln(x)?

toxic meadow
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In(-x) right ?

buoyant kayak
#

that's a reflection

toxic meadow
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f(x+1) ?

buoyant kayak
#

right, which in the ln function would be ln(x+1)

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so now we have our graph translated to the right spot, it now crosses through the origin (0,0)

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but it still doesn't look quite like the ln(x) graph

toxic meadow
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don’t i need to reflect it over the y-axis

buoyant kayak
#

yes :)

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and how do you do that?

toxic meadow
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make x negative

buoyant kayak
#

right

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so what does your ln(x) function look like now?

toxic meadow
#

In(-x+1)

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is there a vertical asymptote or am i tripping

buoyant kayak
#

sorry bathroom

quartz osprey
buoyant kayak
#

oh shoot i thought it had an asymptote at 1

quartz osprey
#

quick lil question

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how am i doing this wrong

toxic meadow
buoyant kayak
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$xln(a)=ln(a^x)$

ocean sealBOT
#

a disappointing son

buoyant kayak
#

so new strategy same concept lol

quartz osprey
#

oh so xlna is ohhh

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i see

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alright

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thyanks

toxic meadow
buoyant kayak
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well, when x is 0, y is 0

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so, y=ln(-x+2), plug in 0 for x and solve for y

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what do you get?

toxic meadow
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2

buoyant kayak
#

not just 2

toxic meadow
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In(2)

buoyant kayak
#

right

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so when x is 0, y is ln(2)... so we can fix that by translating our graph down ln(2) units

pallid void
#

is anyone using this channel

dusk solstice
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This is (0,2)right?

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Or (2,0)

pallid void
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(2,0)

dusk solstice
#

Ok ty

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What would this be

faint elbow
#

x first then y

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and since there are 4 squares between 0 and -2 you can find the number inbetween

dusk solstice
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-1

faint elbow
#

yes

dusk solstice
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What’s the answer

faint elbow
#

You got it

dusk solstice
#

0,-1

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?

faint elbow
#

Well the dot is not on x = 0, so read the x-axis first, and then the y-axis

dusk solstice
#

2,-1

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?

faint elbow
#

yeah buddy

dusk solstice
#

Ok ty

faint elbow
#

That's the standard procedure

dusk solstice
#

<@&286206848099549185>

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14x11x11?

vernal wind
#

Hey can someone explain me this Y = c*Ln(X)+b ?

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It should be the equation for a logarithmic trend line. But i dont what letter stand for?

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<@&286206848099549185>

vagrant falcon
#

where do i even start with this?

edgy sand
#

could someone help me with solving this?

faint elbow
#

derive 8e^y by taking the log of e

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say derivative of y': 2x^y =2x^y * log(x) for the first derivative

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and since you need to do it a second time, its a repeat of the log section, since it doesn't have y in it

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@edgy sand

edgy sand
faint elbow
#

well the log is the derivative of an exponent

forest sage
#

Search the remainder theordm

frail rivet
#

can i ask

paper holly
#

how do we simplify sin(arccos(x)) or cos(arcsin(x))

ivory zinc
#

Just quick clarification on algebriac word problems. Typically when asked for the variable k when it wasn't already provided in the problem, it's the constant correct? In this case "At a constant t the v varies inversely as P" [Then it asks for K and P]

quartz osprey
#

helllo quick querstion

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im kinda confused on this

north needle
#

Ln(e) is 1

quartz osprey
#

well the setup

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like is my setup kinda correct

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so xlne would become x-ln1+x

north needle
#

No? I don’t think you could split the Ln(1+e^x)

quartz osprey
#

so it stays as taht?

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so it would be x-ln(1+e^x)

north needle
#

Yeah

quartz osprey
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youre such a genius thank you

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why cant you split ln 1+e^x though

north needle
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I think it’s cause it’s a function within a function

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Ln(1+e^x) ≠ Ln(1) +x I think

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Yeah Ln(1) is O so the function can’t be split

quartz osprey
#

ok i see thank yuoui

empty snow
#

need help

quartz osprey
#

what do nt you understand

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isnt this just big equation dividison

void solar
#

Do you know remainder theorm

quartz osprey
#

x^2+

empty snow
#

i know factor theorem not heard of remainder

void solar
empty snow
#

so would i get the answer with long division?

north needle
#

You could but it would involve simultaneous equations and be kinda hard to do and higher risk of a mistake

stiff idol
#

idk how

north needle
#

180-

stiff idol
#

?

north needle
#

180-38

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Answer is 2p

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Angles on a straight line sum to 180

stiff idol
#

so is p = 19

north needle
#

Yeah

stiff idol
#

ok

north needle
#

As long as that line is straight

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Which it looks to be

void solar
# empty snow need help

Basically its saying f(x) diveded by 2x-1 = -5
so you can change 2x-1 into x = 1/2
then sub that into the equation and equal it to -5

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then solve

north needle
#

Sub in x = -2 and equate to 0

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Simultaneous equation

brisk sentinel
#

I am having trouble on this problem, and idk how to start it

magic root
#

Write a mixed number and then convert it to an improper fraction. Draw a diagram to confirm your answer is correct.

how would I draw a diagram to confirm this?
<@&286206848099549185>

hushed pasture
ocean sealBOT
hushed pasture
#

solve that system

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$a+b = -2 \ a-b = -8$

ocean sealBOT
dawn glade
#

Question: 4 people pay different amounts for a shared item but want to even out after. What's the formula?

brisk sentinel
# hushed pasture solve that system

When I enter a or b in the answer sections it says "b,a is not defined in this context" I put a=-2-b, a=-8+b and b=-2-a, b=8+a Am i missing something? thank you for helping me

hushed pasture
#

@brisk sentinel wtf??

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anw a = -5, b = 3

brisk sentinel
#

nvm I was being a small brain I figured it out. I was trying to do what you said separately and was getting all messed up. thank you.

hazy knoll
#

?

north needle
#

16k^2 - 12k

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So k( 16k - 12 ) ?

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b = 4k a = 1 and c = 3k

soft sun
#

umm so im dumb can some explain this to me

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someone *

north needle
#

C

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a, b, c are constants
Constants means their value isn’t dependent on x (they don’t change)

So subbing in the co-ordinate gives:
1 = a + b + c

brisk sentinel
north needle
#

-1 as b

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y = 5/2 x + b
4 = 5/2 (2) +b
-1 = b

brisk sentinel
#

thank you!

kindred warren
#

no

prime fjord
#

If $\mathbb{P}(Y ≤ y) = \mathbb{P}(X ≤ y)$, then can I conclude that $X = Y$?

ocean sealBOT
#

egg bird

prime fjord
#

Probability

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I was wonderibg if the random variables are the same

alpine nacelle
#

Not necessarily

prime fjord
#

Ok

#

Ty

wild oar
#

What is the probability that a number between 1 and 119 is a multiple of 2 or 3?

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Does anyone know?

alpine nacelle
#

Can you rephrase your question ?

prime fjord
#

I believe he means is it true that P(X = a) = P(Y = a)?

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However that would imply they are the same random variable I think

alpine nacelle
#

Two variables can follow the same law without being the same variable

sick torrent
#

Why is the second part incorrect?

prime fjord
#

U factored an extra x

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In f'

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Should be 3x(x - 6)

alpine nacelle
#

Nope

sick torrent
#

There’s something else I’m doing wrong I just don’t know

prime fjord
#

Also f = x^3 - 9x^2

#

U substituted it incorrectly

sick torrent
#

Ohhhhhhhhhhhh

#

Thank u

prime fjord
#

Nw

zealous adder
#

What do I do here

north needle
zealous adder
#

7

#

AB

north needle
#

For A do 5! x 5!
It’s looking for combinations

sick torrent
zealous adder
#

I did apparently that's not the answer

north needle
#

So for A since you have 5 possible tens you also have 5 units

zealous adder
prime fjord
north needle
#

Wait no it’s 5 x 5!

prime fjord
#

Get them both right, then the whole answer will be right

zealous adder
#

Why

north needle
#

You can only have the first digit once

#

So you can do 11,12,13,14,15

#

21,22,23,24,25

zealous adder
#

Isn't 5! = 5×4×3×2×1

ashen anchor
north needle
#

Ah

zealous adder
alpine nacelle
#

Random variables are functions, they're equal in the usual sense of function equality, iff they're equal for all values. They don't even have to be the same variables to follow the same law, and if they have different law they can still be coincidentally equal for some value. One equality of proba on some specific value for two different variables and laws doesn't imply anything.

zealous adder
#

Makes senze

#

Thank you

north needle
#

Why was I doing combinations?

ashen anchor
#

no problem, hope my handwriting is understandable

zealous adder
#

Your handwriting is good

north needle
sick torrent
prime fjord
#

Nw

#

Remember all ur trig and algebra

#

You need it for calculus

simple python
#

How do i get from the second to the third line?

gaunt mulch
#

Guys ima try to learn a years worth of calc in one night got any tips for staying up or just in general?

north needle
fresh parcel
#

lol

gaunt mulch
#

Ok thanks ! 🙂 lol

zealous adder
north needle
fresh parcel
zealous adder
north needle
#

For a would it be 5x4x3

#

If you need to make it an even 3 digit

zealous adder
#

A's answer is 60 apparently

fresh parcel
#

oh wait it needs to be even

zealous adder
#

Yer

fresh parcel
#

well then the last digit has to be 2 4 or 6

fresh parcel
#

so then there are 5 choices for the first digit in the number

#

and 4 choices for the second

#

and since the last digit could be 3 different values then you just multiply by 3

#

so

#

5 x 4 x 3

#

is 60

zealous adder
#

Ohhh

fresh parcel
#

the second one is a bit harder

#

as 0 cant be the starting digit

#

but you can just do casework

zealous adder
#

4×2×3?

#

answer is 52 so can't be

fresh parcel
#

mhm

#

so

#

there are 2 cases

#

either 0 is at the end

#

or it isnt

#

if it is

#

then we can do the same thing as last time

#

5 values for the first digit, 4 values for the second

#

so we get 20 for the first case

#

ah wait

#

there are more cases

zealous adder
#

6

#

0,2,6

fresh parcel
#

if 0 isnt inside the number

#

then we get 4 choices for the first

#

and 3 choices for the second

#

crap

#

this is kind of hard to explain

zealous adder
#

..

fresh parcel
#

mb

#

ill really dont know how to answer it in a well explained way

#

maybe ask someone else?

zealous adder
#

Okokok thanks anyway

ashen anchor
#

what was the answer supposed to be?

zealous adder
#

52

north needle
#

Ending is 0:

5 possible starts and 4 middle so 20

Ending is 2:

4 possible starts, 4 middle so 16

4 is exactly the same as 2

32 + 20 is 52

#

Stars means first number and middle is second number

zealous adder
#

So when we see 0 we always have to evaluate it as if there are 2 options?

north needle
#

Wdym?

zealous adder
#

Like if I see 0,2,6,8 I have to make two separate circumstances

#

One for 0 one for not zero

north needle
#

Yes though technically here I made three except the none 0 give the same val

#

So I cba to write out

zealous adder
#

Okokok and if there's no 0 I just use the method fiction showed

ashen anchor
#

oh

#

i did the same thing as @north needle

north needle
#

It’s annoying because of the three digit number

#

Otherwise you could do the same as before

zealous adder
#

If it's 4 digits I do the same thing, yes?

zealous adder
north needle
zealous adder
#

Okok thank u

ashen anchor
#

its just a bunch of case checking which is annoying

#

there's probably a more elegant solution but im too small brain for that

#

lol

ocean sealBOT
alpine nacelle
#

The set of positive integers is itself closed under addition
x, y positive integers, x+y is a positive integer

#

Wait no

#

Idk why I imagined finite subsets I'm so dumb

#

You obviously have ok subsets

#

Like 2Z

#

The subsets of all positive even numbers is closed

#

Under addition

#

Since the sum of positive even number is a positive even number

obsidian scarab
#

L

#

Seems done

alpine sable
#

,w calc

ocean sealBOT
alpine sable
#

,w calc 90/480 * 100

ocean sealBOT
alpine nacelle
#

You also have more trivial examples, like the subset of integers greater than 5

#

Is a subset of positive integers

#

Closed under addition

wary jungle
#

can someone help me figure this out

alpine sable
#

i dont know?

wary jungle
#

ok i want ppl who do know how to help

warm brook
#

@wary jungle I’m assuming that you’re using
[\lim_{h\to0} \frac{f(x+h)-f(x)}{(x+h)-x}]

ocean sealBOT
fresh parcel
#

isnt the bottom just h

warm brook
#

the denominator is just h, but I wanted to write it out completely so it’s change in f over change in x

#

yes

fresh parcel
#

oh

opal reef
#

quick question, with linear functions does it matter if the input is negative or positive?

opal reef
#

if its a function or not

warm brook
#

this channel is taken rn, but no, it shouldn’t matter

alpine sable
#

what are linear functions

#

im grade 8

#

. ¯_(ツ)_/¯

opal reef
fresh parcel
#

like for 5x + 2

#

if the input is negative it changes?

fresh parcel
#

im confused

alpine sable
#

so...

#

if x = 2

opal reef
warm brook
#

no

opal reef
#

ok

#

thought so

alpine sable
#

hm.

fresh parcel
#

still confused but i guess it got answered

opal reef
alpine sable
#

whats the f(x)

#

like you put something into x?

opal reef
fresh parcel
#

lets just write y

#

f(x) means a function of x

warm brook
alpine sable
#

and whats the function

#

for

opal reef
alpine sable
fresh parcel
#

im in 8th grade too, don't you learn it there

alpine sable
#

/ ¯_(ツ)_/¯

fresh parcel
#

pretty sure its like curriculum stuf

#

oh bruh

opal reef
alpine sable
#

i will google it myself

fresh parcel
#

its better to learn stuff now than later

warm brook
fresh parcel
#

if you know calc by gr8 you'll pretty much be fine

fresh parcel
#

ye

opal reef
#

who knows calculus in 8th?

#

ik people in pre alg in 10th

zealous adder
fresh parcel
warm brook
#

so how many more bears are there than earlier

zealous adder
#

What do I do here

fresh parcel
#

i was bad at math before quarantine but quarantine gave me a chance to learn

#

70%

warm brook
#

yes, so what’s the percent gain? So if there are 7 more bears when there used to be 10..

fresh parcel
#

increase

warm brook
fresh parcel
#

ik

#

im going to explain

opal reef
warm brook
#

uh oh

warm brook
#

I-I know

ocean sealBOT
alpine sable
#

ok so

#

IF

#

shelby could run 4 miles now

#

its 2 times the distance she could run at the beggining of the year

#

which is 200%

#
  • 100 %
#

but this is 3.5 miles

#

so we notice that 2 + 4*(0.5) = 4

warm brook
#

the integers form a ring, so yes, as long as the subset also forms a ring (which you can prove is always)

alpine sable
#

and 2 + 3*(0.5) = 3.5

#

so

placid zinc
#

Any subset of Z under an associative operation, yes.

alpine sable
#

we can divide 100 by 4

#

25%

#

so 3.5 miles is 2 miles + 3*0.5miles = 3.5miles

#

then you go for it

#

+75%

#

you gain nothing by getting the answer

warm brook
#

The amount gain is the final - initial, then the percent gain is (final - initial)/initial * 100

alpine sable
warm brook
#

so if final = 3.5 and initial = 2.0..

alpine sable
#

Anyone mind explaining this to me? Why does it being a constant term make it 0?

#

Dont get how k=-3 either

#

so 75%

#

\ ¯_(ツ)_/¯

warm brook
#

it’s okay they’re trying, they’re in 8th grade, I appreciate their commitment to at least trying to help

alpine sable
#

k

radiant barn
#

Hrlp

fresh parcel
alpine sable
#

if you dont know how to do just remember this formula

#

(final - initial)/ initial)) * 100

alpine sable
#

ok here

#

so

#

no do the - first

warm brook
#

yeah so the idea is not to divide by 10, but rather you take the difference (15-12=3) and divide it by 12, which was the first number of laps

alpine sable
#

so final is 15 and intitial is 12

#

15 - 12 = 3 and divide by initial 12

#

0.25

alpine sable
#

so its 25%

#

@wooden walrus

#

yeah

fresh parcel
alpine sable
#

but not always

alpine sable
#

yeah how much percent he gained

fresh parcel
#

nono

#

k isnt 0

#

the overall constant has to be 0

#

like after you add everything

#

the constant doesnt refer to k

alpine sable
#

In this scenario

fresh parcel
#

so the overall constant must be 0

#

or else x wont factor out

alpine sable
#

So the only thing to assume is that its 0

fresh parcel
#

just try that first

alpine sable
#

Ok I get that part

fresh parcel
#

then because it has to be divisible by x

#

you divide every single part by x

warm brook
fresh parcel
#

correct?

alpine sable
fresh parcel
#

but you'll see that theres a 15

ocean sealBOT
fresh parcel
#

and 15 is not always divisible by x

#

so you need to get rid of that constant

warm brook
#

So you’re not getting buried I can explain in DMs

fresh parcel
#

you'll also see that at the end theres a 5k

alpine sable
#

Mhm

fresh parcel
#

so the only 2 terms that dont factor out are 5k and 15

alpine sable
#

Yes Yes go on

fresh parcel
#

therefore, the best way to make sure the whole term is divisble by x we need 5k and 15 to cancel out

alpine sable
#

Ah I see

#

Now I get it

fresh parcel
#

now think: What does k need to be such that 15+5k = 0?

#

now you can easily see its -3

#

:)

alpine sable
#

I GET IT NOW

#

Tysm

#

.

slim sun
#

can i get help

alpine sable
#

oops

ocean sealBOT
#

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

warm brook
#

yes

#

Although it’s Q, think about the fractions..
1/2 is in the equivalent class for 2/4,4/8,etc.

#

so same works here

#

well, i don’t like the 1/2 neq 4/8, but in some way yes

fresh parcel
ocean sealBOT
warm brook
#

not really i don’t think

maiden saffron
#

Hey

#

I need texcit

#

How do i make slope problems

#

Nvm

alpine nacelle
#

Z_n is another notation for Z/nZ, these are modulo

#

The class of 0 has the elements that are equivalent to 0 mod n

#

But you'll probably see it further in the book

#

You can write the class of x as

#

$\bar x$

ocean sealBOT
#

Mélo

alpine sable
#

Hello, how should I use the chain rule for deriving this?

#

I first tried to split it up into 3 separate functions.

f(x), the outer function: 3x
g(x), the middle function: 3x^2-4
h(x), the inner function: 1/x

#

but when i tried to apply the chain rule, I couldn't apply g(x) to f'(x), since f'(x) is just 3.

#

no variable to apply it to.

sour dove
#

yes you'll need chain rule but only for one thing

#

I would distribute out the 3 first. What do you get?

alpine sable
#

9((1/x)^2)-12 ?

sour dove
#

yep perfect!

#

So next youll need the chain rule. What do you think it'll be?

alpine sable
#

9x^2-12

sour dove
#

not quite

#

so we're deriving with respect to x

#

our only x is 1/x

#

but it's wrapped in a power of 2

#

now there are 2 options:

#
  1. You can distribute the square and turn it into 1/x^2 which is x^-2
  2. You can do the chain rule of (1/x)^2, which would be 2* (1/x) * (1/x)'
#

the -12 will go away since d/dx(-12) = 0

#

can you get it from here? 🙂

alpine sable
#

ill give it a go

#

thanks

#

Can I ask my question till then @alpine sable

sour dove
#

@alpine sable feel free to ping me when you're at a place or get stuck

alpine sable
#

sure cosmos

ocean sealBOT
craggy niche
#

Is this channel busy?

#

Doing a paper on correlation of two functions. Easy, issue is finding a dependent/independent variable. Independent cannot be time. Example was affect of time (years) on iPhone sales after 2007. Sales went up.

dreamy flint
#

bruh

zealous adder
#

How do I do this omg

#

13 c

alpine sable
placid zinc
#

@zinc cosmos
In order to prove two sets are equivalent, you prove that each is a subset of eachother. That is:
If x is a member of [k] + [l] then it is also a member of [k + l]

And if x is a member of [k + l] then it is also a member of [k] + [l]

alpine sable
#

lil help

ocean sealBOT
placid zinc
#

Good, that's the hard one haha

ocean sealBOT
placid zinc
#

It doesn't, and that's not usually true

#

a + b ∈ [k + l] is the smart statement

ocean sealBOT
placid zinc
#

No no. It shows that, if you choose any element in [k], and any element in [l] and add them together, you have an element in [k + l]

#

That is, you can add the representatives, rather than the elements themselves

#

I can make it concrete.
What's 202 + 2002 (mod 4)?

#

You can actually add those together, then reduce...

But you probably reduced first, then added them

zealous adder
#

For B I did 6P2 but C idk where to start

peak kite
#

Helpo

#

Help

placid zinc
#

We're proving that doing the reduction first is legal

peak kite
#

I neeed help inaths question

#

Who can help mr dm me

#

Pls

#

Maths

#

Marc urs tough

#

If y can help

#

U

#

Dm me

placid zinc
#

Okay! Hopefully it helps. Feel free to ask if you need anything else with it

red mirage
#

are there any dedicated tutors on this server?

peak kite
#

Can somone help me with maths

#

Of u can pls dm me

sour dove
#

@peak kite if you have some specific question post it here and helpers will help you. But it's on a per problem basis

red mirage
#

Looking for help with Math 169 trades mathematics 😫

sour dove
#

@red mirage see above. If you have a specific question feel free to post

red mirage
sour dove
#

but people helping do it on a volunteer basis, so it's a per question basis

red mirage
#

thank you!

midnight girder
#

hello!

#

could someone explain implicit differentiation

#

we have to self learn this concept b4 class and im a bit confused

#

how is it different from the basics of differentiation?

sour dove
#

@midnight girder implicit differentiation is super fun!

#

so whenever you take a derivative of something, say y = x^2

#

then you get (dy/dx) = 2x right?

midnight girder
#

right!

sour dove
#

but what if you wanted to take the derivative of something, say y^2 = x^2 + sin(x)?

buoyant kayak
#

it's taking the derivative treating y as a function of x

sour dove
#

if we're taking something the derivative with something with respect to x, then we need to manipulate something that is not x as well

#

so typically how that looks is of the form d/dx (y) = (y)'(dy/dx)

#

and we can see that in action with just a single y value!

alpine sable
#

can anyone explain derivatives

sour dove
#

y = x^2 using implicit derivation is (y')(dy/dx) = (x^2)', or 1*dy/dx = 2x

buoyant kayak
#

slope of a line at a point

alpine sable
#

im trying to understand

sour dove
#

so believe it or not, you're already doing implicit derivation without even realizing it!

alpine sable
midnight girder
buoyant kayak
#

is derivative

alpine sable
#

no

#

dont click it

#

NO

#

thats why you dont click it

small cypress
#

how do u find the median here

sour dove
midnight girder
#

@sour dove if for a problem where the y is not already isolated, would we have to isolate it first?

small cypress
#

<@&286206848099549185>

alpine sable
buoyant kayak
#

the point of implicit differentiation is that you don't need to isolate y

#

sometimes it's impossible to do so

midnight girder
#

oh i see

alpine sable
# small cypress

In statistics and probability theory, the median is the value separating the higher half from the lower half of a data sample, a population, or a probability distribution. For a data set, it may be thought of as "the middle" value. The basic feature of the median in describing data compared to the mean (often simply described as the "average") i...

sour dove
alpine sable
#

im 8th grade

sour dove
#

I would start with that then

#

but basically you know the equation y = mx + b?

#

we know the slope is m, right?

alpine sable
#

no idea

sour dove
#

oh

buoyant kayak
#

an 8th grader does not need to know derivatives

sour dove
#

well I think you probably need to build up math foundations first

alpine sable
buoyant kayak
#

algebra lmao

#

precal

#

basic geometry

#

trigonometry

alpine sable
#

damn i learned algebra when i was 5

sour dove
#

most mistakes made in calculus (aka where you use derivatives) are algebra mistakes

midnight girder
#

@alpine sable derivatives is a whole new concept

#

it has its own set of rules but once you learn it, it gets really easy!

#

its the same like 4 rules applied over and over

peak kite
#

Anyone that can help me in maths

buoyant kayak
#

probably not

peak kite
#

8th grade maths

#

The sum of two numbers is7/20.If one number is 1/4 then other is

rough salmon
#

Bruh

#

7/20-1/4 will get u the ans @peak kite

peak kite
#

Oh

rough salmon
#

The ans goin to be negative tho

#

Cos 7/20 is smaller than 1/4

buoyant kayak
#

no it isn't

peak kite
#

1 by 10 right

wary stream
peak kite
#

I have done

rough salmon
#

Oh

peak kite
#

I need confirmation

#

Is 1 by 10

rough salmon
buoyant kayak
#

1/4 + some other number is 7/20

rough salmon
#

Ya

#

Lol

#

Careless

buoyant echo
#

how is this channel so populated lma

buoyant kayak
#

so $\frac14 + x = \frac{7}{20}$

ocean sealBOT
#

a disappointing son

buoyant kayak
#

solve for x

peak kite
#

Done

buoyant echo
#

am needing help

peak kite
#

1/10

wary stream
buoyant echo
#

how do i use the bot

wary stream
#

Yes

buoyant echo
#

yo how do i use that bot

peak kite
#

In a Rhombus ABCD ,if the measure of <A=50degrees then find the measure of <ADC

#

What about tis

past sleet
#

just ask the question spamton

rough salmon
#

I have a question too
Let's say I HV a num 80
a * b * c must be equal to 80
How many combinations r there of the values of a, b and c considering 2, 20, 4 and 4, 2, 20 is the same

peak kite
#

Do

wary stream
#

Can you draw?

#

Because draw a diagram

peak kite
#

Okay

#

Wht us standard form of 1234000 is

#

Also what is depricet

#

@wary stream

#

What is depricet

#

Or sumthing

#

Hello

#

<@&286206848099549185>

buoyant kayak
#

not a word in the english language

alpine sable
#

what's the answer

shy thicket
#

WHAT THE ANSWER NOW 😡

buoyant kayak
#

use the formula for sum of a series

placid zinc
#

What are you allowed to use? Do you know sigma notation?

alpine sable
#

this is from the 2020 oxford mathmatics admission exam

#

I have no idea what sigma notation is

buoyant kayak
#

why are you taking the 2020 oxford mathematics admisison exam

peak kite
#

Find the depreciated value of a rikshaw after two years  whose present cost is RS.144000 and rate of depreciation is 5/2% p.a.

placid zinc
#

Practice I assume

alpine sable
#

to get a sneak peak of what I will hopefully take when I go to uni

placid zinc
#

Never too early to learn sigma notation, as it makes problems like this easy

alpine sable
#

are you a math teacher

peak kite
#

Somoje help me

#

Pls uwh

#

Uwu

#

Find the depreciated value of a rikshaw after two years  whose present cost is RS.144000 and rate of depreciation is 5/2% p.a.

alpine sable
#

*UwU

peak kite
#

UwU

placid zinc
#

No haha I've never taught professionally

alpine sable
#

also what do the ... mean

#

oh

peak kite
#

Somone help me

#

0lllls

#

Plls

#

Pls

alpine sable
#

also what is the best way to get advanced in math

peak kite
#

Find the depreciated value of a rikshaw after two years  whose present cost is RS.144000 and rate of depreciation is 5/2% p.a.

alpine sable
#

self learning

#

oh shit psat tommorow ._.

placid zinc
#

Actually, I can think of a good solution you should be able to work with. Every two terms of this sum are of the form:
n² - (n + 1)²
= n² - n² - 2n - 1
= -2n - 1
So you can sum that for all odd n

alpine sable
#

that's called sigma notation?

placid zinc
#

No no I haven't included it haha

alpine sable
#

oh

#

can I ask you