#help-0

1 messages · Page 864 of 1

flint badger
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"Make this side 0"

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now u can do that

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x^2 + 10x + 9 = 78 right

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thats what it is now

barren river
#

no u used an example and so do i

flint badger
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oh

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im confused

barren river
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a

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x2+4x-3x-12

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x2+x-12=78

flint badger
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no thats not the right way to do it

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u did it dight here

barren river
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one sec

flint badger
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oh my god wait I just realized how stupid that was

barren river
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X+4(x-3)

flint badger
#

u got it

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nvm

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@barren river u are right

barren river
#

bruh

flint badger
#

I forgot about original question XD

flint badger
#

do u know what to do next

barren river
#

u said move the 78 to the left side

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So it would be negative 78

flint badger
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wait omg @barren river bro

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this is so confusing, sry

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(x-4)(x-3)

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do this again

barren river
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its (x+4) tho

flint badger
#

bruh

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i wrote it wrong

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ims uch a bad teacher

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ok I guess ur right then

barren river
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now u made me confused

flint badger
#

no

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u were right

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dont listen to me

#

u did it right, I just thought it was x-4 so I got confused

flint badger
barren river
#

wdym

flint badger
#

remember u have to make right hand side zero

barren river
#

oh "what will this become"

flint badger
#

To solve the quadratic right

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u are trying to solve for x, remember?

barren river
#

yes

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yea uh

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Confirming

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X=9 or x= negative 10

flint badger
#

yes @barren river

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now let me ask u

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@barren river if u plug x back into the original triangle, which will make more sense

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9 or -10

alpine sable
#

sorry but what am i supposed to do here?

ashen anchor
#

More context to the question please?

alpine sable
#

find the value of the area of the triangle

flint badger
#

This is altitude problem right

fickle swift
#

Hi, can anyone help me with this question?

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ABCD is a rectangle
AB: 5 cm, BC=3,6 ​​cm
AM+BM= 13 cm
Required: calculate the perimeter of △AMD

ashen anchor
#

What have you tried?

fickle swift
#

The teacher gave me a hint and said that we have to use Thales and his hourglass theorm "idk what it's called in english" and also the Pythagorean Theorem

ashen anchor
#

You have to? I can probably solve it using other methods

fickle swift
#

i might find MD by using Thales and then find AM by using the Pythagorean Theorem easily

fickle swift
#

i was talking about this

real crescent
#

hi can someone tell me if this is correct please

arctic wren
frank fable
fickle swift
ocean sealBOT
fickle swift
#

where

arctic wren
#

i didn't go that far, but as far i looked at it and remember my geometry classes would do that way

real crescent
fickle swift
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I mean we don't have Y in the shape

arctic wren
sick sorrel
#

can someone help me find the slope - rate of change

alpine sable
ocean sealBOT
#

Quod Erat Demonstrandum.

sick sorrel
#

omg tysm 🤗

alpine sable
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No problem!

ocean sealBOT
alpine sable
# real crescent hi can someone tell me if this is correct please

These type of questions actually feel paradoxical to me to be honest. Like the principal will change every 1 year or "triple the original sum" by that do they mean amount or internet? If they mean amount, we have to calculate interest as 2x else we would have to calculate interest as 3x. If you get what I mean.

tight birch
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hello, if i have a variable inside an integral which is not related to the differential, can i just take it out?

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in this case, x if not a function of y

alpine sable
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in this case, yes, you can

tight birch
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oh so it's like the thing in partial derivatives, where the "unrelated" variables can just be taken out the derivative sign?

alpine sable
#

exactly

tight birch
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hmmm okay okay thanks

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so this is still fine right

alpine sable
#

if neither of A, w or t is in function of v or vice versa, yes, you can

tight birch
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💯 thanks!

ashen anchor
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its using some analytic geometry

fickle swift
jovial terrace
#

Can someone explain to me how we get to the answer (answer will be in the image below this message) when downsizing this?

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I just can't get to that solution

devout summit
jovial terrace
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How?

devout summit
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4x=(2x)*2 and, 6x+2x^2=2x*(3+x)

devout summit
jovial terrace
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oh

charred nacelle
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can someone explain why it's 21 and not 32

wind venture
#

Pretty simple

jade birch
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$5^{21}\cdot 2^{22}=5^{21}\cdot 2^{21} \cdot 2 = (5\cdot 2)^{21} \cdot 2 = 2\cdot 10^{21}$

ocean sealBOT
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.itsjustnai

high bear
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hi can i get some help once everything is free'd up here

charred nacelle
#

I know it's the same value

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Is this something I should just 'know'

devout summit
#

$4^{11}=\left(2^2\right)^{11}=2^{2\cdot 11}=2^{22}$

ocean sealBOT
#

Euclid31415

jovial edge
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Hi

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How do I calculate this?

warped phoenix
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thank you!!

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now another question 😅

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I dont see why this is wrong

vagrant dust
# jovial edge How do I calculate this?

The player would need to require only 1 set to win the match. So if we calculate the probability of the player losing all matches(1/2 * 1/2 * 1/2) and then subtract it from 1 u will get ur answer.

fiery berry
#

?

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How would I solve this without log

jovial edge
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How about this one?

ruby badger
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Did i do the 1. And 2. Correctly?

novel siren
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you forgot 7 in the first one

ruby badger
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Oh yeah

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But i did 2. Correctly right?

novel siren
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yes

azure gorge
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hey i got 2 very amateur almost ridiculous math questions:

a) I pick 2 flowers every 17 seconds, how many flowers would i pick in 1 hour?
b) I pick 3 flowers every 17 seconds, how many flowers would i pick in 1 hour?

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how do i solve this?

lapis wigeon
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you have to figure out how many seconds are in hour

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and then divide the time it takes through the total time you have

azure gorge
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1 hour = 3600s
using the rule of three formula.

a)
17s = 2 flowers
3600s = x flowers

2 * 3600 divided by 17 = 423.53

I get approx. 423 flowers in 1 hour.

b)
17s = 3 flowers
3600s = x flowers

3 * 3600 divided by 17 = 635.29

I get approx. 635 flowers in 1 hour.

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@lapis wigeon is this correct?

lapis wigeon
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yes

azure gorge
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thanks

pine igloo
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anyone able to help me with differential equations (ODE)?

alpine sable
severe marlin
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Anyone evaluating this without calculator easily?

obsidian crane
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Oh wait that's not a power inside

alpine sable
obsidian crane
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So , it becomes (25/4)^-3/2

obsidian crane
severe marlin
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Go on

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I’m on that part right now

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but continuing is a problem

obsidian crane
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Now you notice theres 1/2 in the power

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that's square root

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so it becomes

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(5/2)^-3

severe marlin
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but it’s a negative power

obsidian crane
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now reciprocal

obsidian crane
obsidian crane
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8 / 125 final answer

jovial tulip
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i need help with a geometry problem

severe marlin
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yes you are correct can you explain again

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so what will become 25/3

alpine sable
#

My bro here is helping.

jovial tulip
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ok

obsidian crane
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you mean 25/4

severe marlin
jovial tulip
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i didnt say anythig

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tho

obsidian crane
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Just apply the power

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2x2x2/5x5x5

severe marlin
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I’m at (25/4) power -3/2 so far

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What shall I do after

obsidian crane
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Look

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(25 / 4)^-3/2 = (((25 / 4) ^ 1/2) ^ -3)

Do you understand this ?

severe marlin
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can you write it out?

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I can’t understand the computer signs

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Sorry to put you through this

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I should know this

jovial tulip
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^ = power

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ok can i ask now tho?

severe marlin
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@jovial tulip just a tip there are question channels up to 9

jovial tulip
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ok

severe marlin
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if they don’t reply here

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Try the others

alpine sable
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Wrong quote though

obsidian crane
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@severe marlin

alpine sable
#

Meant to quote the geometry dude

severe marlin
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@obsidian crane cheersss man

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Appreciate that

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lemme work that out

obsidian crane
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👍

severe marlin
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Lovely

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Thanks king

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I understand more if I see the questions written

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And that’s very helpful

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Appreciate that, correct answer aswell

ember tartan
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can someone help me

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..

severe marlin
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@obsidian crane

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Does it also work the same for the others

obsidian crane
ember tartan
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MB mb

obsidian crane
severe marlin
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Typically this one

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just the same one basically

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Without the negative power

obsidian crane
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Yes it will work.

azure badger
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guys unrеtard for a second pls

severe marlin
#

Also note we can’t use calculators

azure badger
#

Let P (x) be a square polynomial. The equations P (x) = x-10 and P (x) = 1-x / 10 have 1 solution. What is the discriminant of P (x)?

alpine sable
#

Bruh.

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There are two pending questions my bro.

obsidian crane
#

It's a general rule
$(a ^ x)^y = a ^ xy$

severe marlin
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@obsidian crane how is the procedure any different this time on this one? Fo you think you can write it?

obsidian crane
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$(a ^ x)^y = a ^ (xy)$

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uhh lol

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sec

severe marlin
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Just write it out lmao

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the bot is hard

obsidian crane
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Just remember this rule

severe marlin
#

Ty

alpine sable
#

Is there a way of simplifying $$-\frac{\left(x-n\right)}{f'(n)}+f(n)=\sqrt{f\left(\int_{0}^{n}\sqrt{1+\left(\frac{df(x)}{dx}\right)^2}dx\right)-\left(x-n\right)^2}$$?

ocean sealBOT
alpine sable
#

I just had this math shower thought in which I rectified the curve of a continuous function and applied that function over itself as if the curve was the axis of the independent variable, then de-rectified it , preserving angles and distances at best

lofty bluff
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guys I have a question

alpine sable
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Bruh

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Do it.

lofty bluff
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is this correct?

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cos²(πx) = cos(πx)²

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?

obsidian crane
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no

alpine sable
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Why?

tight birch
lofty bluff
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it is right?

azure badger
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do you mean squared argument?

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or what

lofty bluff
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the square is afecting the cos too?

obsidian crane
lofty bluff
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yeah

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for the square to affect only the πx

tight birch
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$$cos²(x) = cos(x) cos(x) = (cos(x))²$$

ocean sealBOT
lofty bluff
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it should be cos((πx)²)

lofty bluff
tight birch
#

same with all trigos\

lofty bluff
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then how do you make the square only affect the πx

obsidian crane
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can you give me an example where you would need to do that ?

lofty bluff
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I am having an argument with a teacher

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where she says that cos(πx)²

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is only affecting the πx

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but not the cos

tight birch
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she's right

obsidian crane
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wait it must be cos((πx)²)

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brackets matter

lofty bluff
#

thats the debate

novel kettle
#

Can someone check if I did this right
Question: A shopkeeper bought 300 apples at 80c each.30 apples got rotten and the remaining were sold at the market for 20c each.
A: Find the buying price
B: Find the selling price
C: Find the gain or loss percent

tight birch
#

if you want to affect the πx only then she's right

lofty bluff
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hmmm

tight birch
lofty bluff
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i also think that it should be cos((πx)²)

tight birch
#

ya ya agree

lofty bluff
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then my statement of cos²(πx) = cos(πx)² is not correct

alpine sable
#

does slope include x?

tight birch
#

no

obsidian crane
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x is a variable

alpine sable
#

ok

lofty bluff
#

well

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thanks

forest orchid
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can someone help me solve this, i dont really understand how to do transformations

waxen copper
#

help

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please

novel loom
#

to make sure
15x^5
----- (over)
3x^2
= 5x to the power of 3

buoyant kayak
#

yes

ember tartan
#

god...someone help me

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._.

buoyant kayak
#

with?

ember tartan
compact nexus
#

I'm unsure where to post this, but would someone be able to help me observe the general case? I don't see it intuitively

crimson blade
#

i was watching a yt tutorial on how to answer a question, and he converted x to a half and im unsure why or how he did it. does anyone know?

alpine sable
#

you use u-substitution where u = x^2 + 1, which means du = 2xdx, so dx = 1/2 du

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then you have $\int \frac{1}{u} \cdot \frac{1}{2} du$

thorn kindle
#

Wow

crimson blade
ocean sealBOT
#

bertaunth

lethal lichen
#

can anyone help me with part B?

#

im using the formula for the sum of n terms in a geometric sequence

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but my answer using this formula is wrong

toxic cave
#

How can I convert an answer in mapping notation to its logarithmic form?

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Mapping notation: (1/2x,y)

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The answer which idk how to get: y=log2x

mild plover
#

If a question is
dy/dx | x=-1

Do I input x =-1 into the derivative?

mild plover
#

So this just means find the Y value of the derivative at -1?

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Slope of tangent line at that x value

alpine sable
#

yes

mild plover
#

Thanks!

fringe jungle
#

Can someone help with this?

toxic cave
#

Can someone help me with question 16b?

alpine sable
ebon ore
#

guys i need help pls help me find the total distance christopher columbus travelled on his journey

alpine sable
ocean sealBOT
#

bertaunth

alpine sable
#

Bertaunth, excuse me, but is there are topic that deals with streching graphs?

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its the transformation of logarithmic functions

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oh wait no that's for logarithmic funtions

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its just transformations

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Hmmm

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So if I want to learn more about this subject I can just search mathematical transformation on google?

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when we transform something, we can transform it by stretching, moving it, rotating it, etc.

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yep

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Thanks

alpine sable
#

where k is the horizontal stretch/compression

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so if we want to stretch something by 3, we say k = 1/3

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which is where the 1/3 comes from

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now we want to move something to the left by 9 units

alpine sable
#

so d = -9

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so then we get \
$y = \log(2(x-3+9))$

ocean sealBOT
#

bertaunth

alpine sable
#

the we have 6/3 here which is why there's a two in place of the 1/3 and the 6

alpine sable
ocean sealBOT
#

bertaunth

alpine sable
#

@toxic cave

slate kayak
#

Is this correct

alpine sable
#

and then you simplify

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oh wait

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no sorry

slate kayak
#

How do I simplify😅

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Oh

alpine sable
#

i just realized you multiplied by the conjugate

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sorry about that

slate kayak
#

Its ok

alpine sable
#

yeah it looks right

slate kayak
#

Thnx

buoyant kayak
#

which ones do you need help with

#

mmmmk

#

what is velocity in relation to position?

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how do we get to velocity from position?

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right

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and we want the velocity to be zero

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you're given position graphs

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so when is the velocity zero?

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if velocity is the derivative of position

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?

alpine sable
# slate kayak

wait no sorry you have to redo the calculations in the numerator

buoyant kayak
#

what does the derivative represent?

#

what

flint badger
#

what do you mean by

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"after the main one"

buoyant kayak
#

have you taken calc?

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so what is a derivative?

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that's derivative notation

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what is a derivative

#

what is the definition of a derivative

flint badger
#

lmao

buoyant kayak
#

lmfao

flint badger
#

just explain to him what it is man

#

refresh his memory will ya

buoyant kayak
#

slope of an equation at a point...

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ring a bell?

flint badger
#

you're right when you say its an equation

buoyant kayak
#

so knowing that velocity is the derivative of position... when is velocity zero?

flint badger
#

lol

elfin talon
# buoyant kayak what is the definition of a derivative

You can define it as the instantaneous rate of change in a function of time(or any function for that matter), although this definition is conventional and gets the job done, 3b1b called the phrase “instantaneous rate of change” oxymoronic

buoyant kayak
elfin talon
buoyant kayak
#

i didn't have one

flint badger
#

what is the definition of a derivative

#

I thought he was about to give the

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difference quotient

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lmao

buoyant kayak
#

in terms of slope of the position graph

flint badger
#

anyway im gonma leave now have fun

buoyant kayak
#

when is velocity zero

elfin talon
#

I was gonna say that, good on you

elfin talon
#

(By definition)

buoyant kayak
#

bro

flint badger
#

LOL

buoyant kayak
#

not my question lmfao

#

no

#

your answer was not correct

elfin talon
#

What

buoyant kayak
#

no

elfin talon
#

Actually bro

buoyant kayak
#

this is an exam?

elfin talon
#

If you think about it the position is constant at all the points

buoyant kayak
#

welp

alpine sable
#

bruh

buoyant kayak
#

that ain't allowed

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okay

#

<@&268886789983436800>

elfin talon
sly mantle
#

b&

buoyant kayak
#

:)

flint badger
#

damn

#

LOL

alpine sable
#

holy shittt

flint badger
#

I was about to lose my shit when you asked him the "definition of a derivative"

elfin talon
#

Eggdog I know somebody who has your exact name

#

Wierd

#

And he had a pfp similar to yours

flint badger
#

well yea if hes an eggdog

#

he'll probably have an eggdog pfp, but this isnt the place to talk about it so anyway

elfin talon
#

Is it a thing?

flint badger
#

yea its kinda a meme

elfin talon
#

Ohh damn ok

#

Why did he leave

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/get banned

#

I was gonna tell him

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It was gonna tell him it’s a trick question the position is constant at all the points

flint badger
#

You cant get help

#

On a quiz

buoyant kayak
#

he got banned for offering money to complete his exam, and his question was not a trick question

#

it had a very obvious answer

elfin talon
buoyant kayak
#

not in the slightest, no

toxic cave
onyx flower
#

can 3sinxcosx be written as 3/2sin(2x)?

#

or nay

south lava
#

Can someone find the points of multiplicity for the question f(x)=2x^3 - 3x^2 - 3x + 2

alpine sable
south lava
#

thank you

unborn sleet
#

Hello guys I’ve a question about the two’s complement of numbers like -4.25

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How can I represent it, around internet I can’t find anything about the fractional part

#

Someone says that it has to remain as the normal binary conversion other says that it has to be complemented

onyx flower
#

nvm im just dumb

alpine sable
#

sin2x +2xcos2x

shut temple
#

Chain rule my dudes

onyx flower
#

yeah i realized xd

#

clod hands just mistyping

azure badger
#

hello guys can you help me with 1 problem

molten elk
molten elk
# molten elk

How exactly did that go from the line before the underlined line to the underlined line?

molten elk
dry echo
#

Here's my problem

#

This is my work

#

Did I do this correctly? If so, what should I be plugging in besides 0?

#

-4 and 4?

dry echo
#

Nevermind then ✌️

alpine sable
#

when some says "root over 9b minus c" how do you know if they mean √(9b-c) or √9b-c

#

what is the difference in speech?

buoyant kayak
#

$\sqrt{9b-c}$ could be said as the square root of the quantity 9b-c

ocean sealBOT
#

a disappointing son

oak chasm
unborn sleet
oak chasm
#

Similarly, the twos complement of -4.25 is:

-4.25 = 1011.1100
4.25 = 0100.0011 + 0000.0001 = 0100.0100

#

That's not a very wise move, as it will be slow.

#

CPUs are very fast at flipping the bits and adding 1 to the end to do twos complement.

unborn sleet
#

I completely understood your first explaination, the difficult part is why some people leave the fractional part untouched

oak chasm
#

There, you're flipping part of the bits and then adding 1 to the integer part, which isn't at the end, which is two operations instead of one.

#

I assume they just guessed at how it works.

#

It also makes dealing with negative numbers a real headache.

#

You have to handle the integer part and fractional part separately.

unborn sleet
#

Yeah

oak chasm
#

You have to make sure to manually carry if the fractional part overflows.

#

You have to borrow if the fractional part overflows the other way when subtracting a positive or adding a negative.

unborn sleet
#

So I have to think it as two different numbers, factional and integer part

oak chasm
#

You shouldn't.

#

That's not how they do fixed point arithmetic.

#

They treat it as an integer multiple of two to some negative power.

#

So, the power of two goes into the denominator.

#

Like integer multiples of 1/2 are 0000000.1 for example as 1/2.

#

Or 0000001.1 as 3/2.

#

Then addition and subtraction, you can use the standard integer instructions.

#

Multiplication and division, you have to adjust a bit with a bit shift.

#

These are very fast if you keep the integer and fractional part as one number you deal with together rather than two parts.

unborn sleet
#

So let’s say I have 3.5, to represent -3.5 I get first 0011.1000 then flip the bits and add one to get 1100.1000

oak chasm
#

0011.1000
1100.0111
1100.1000

#

Yes.

unborn sleet
#

I think treating the integer and fractional as tel numbers is very complicated

oak chasm
#

Yes, it adds a lot of work to treat them as two numbers.

unborn sleet
#

Cause if I do it for -3.5 I would get 1101.1000 that would mess up

#

They asked me to do with that method but I can’t wrap my head around that

#

It becomes too complicated

#

But if I have to do that, how could I subtract the fractional part

oak chasm
#

Well, you do it like on paper, with one change.

#

That has four digits past the binary point, so it's 1/16ths.

unborn sleet
#

Sorry, what do you mean with one change?

oak chasm
#

Well, you treat it as an integer multiple of 1/16.

#

So, let's say you have xxxx.1000 - xxxx.0100.

You do 1000 - 0100.

#

You check if it borrowed.

#

If it did, you borrow from the integer part's result.

#

Just like you'd borrow on paper.

unborn sleet
#

Dang so I have to treat the integer part as an addition but the fractional part as a subtraction?

#

If I understood

oak chasm
#

No, you subtract both.

#

But separately.

#

Then, you get the integer part first.

#

Then, you get the fractional part.

#

If the fractional part borrowed, you subtract one from the integer part's result.

#

You can tell if it borrowed if you're doing a - b and b > a.

#

Or you can use a CPU overflow flag.

#

If you're closer to the metal.

unborn sleet
#

Damn I think they’re making us do that since we will use CPU overflow flags in a few weeks

oak chasm
#

But never do this in real code if you can avoid it.

unborn sleet
#

Yeah, for sure

oak chasm
#

Treat the whole thing as one integer times a negative power of two.

unborn sleet
#

That would be a waste of time and too complex

#

You’re a saint @oak chasm

#

So let’s say I have
+4.25 = 0100.0100
-4.25 = 1100.0100

#

I subtract them

#

Right?

oak chasm
#

Yes, the integer parts first.

unborn sleet
#

I have to borrow

#

A 1

oak chasm
#
    0100
  - 1100
11110000
#

And then you subtract the fractional parts.

alpine sable
#

may i ask which topic y'all discussing

unborn sleet
#

So I repeat the ‘borrow’ beat?

#

Two’s complement @alpine sable

oak chasm
#
  0100
- 0100
  0000
clever mountain
#

binary?

oak chasm
#

So, you get 0000.0000.

unborn sleet
#

Yeah, @clever mountain

clever mountain
#

ah, cool

alpine sable
#

Oh cool

oak chasm
#

Yes, a method of doing subtraction with a strange representation of fixed point numbers.

unborn sleet
#

Damn, you’re the GOAT @oak chasm

alpine sable
unborn sleet
#

One last question and I’ll try not bother you again

#

0
-1

#

We have to borrow

#

But where do we borrow it?

#

It may sound as a super stupid question

oak chasm
#

What are the full 8 or whatever bits?

oak chasm
#

This?``` 0000.0000

  • 0000.1000
unborn sleet
#

Sorry no

oak chasm
#

Oh, for the integer part?

unborn sleet
#

Yes

oak chasm
#

OK, those are the fractional parts.

#

So, let's do a problem like that.

unborn sleet
#

For the integer part

#

Ok, give me one and I’ll try to solve it

oak chasm
#
    0100.0100
  - 1100.1000
11110000.xxxx

That's what we get for the integer part.

unborn sleet
#

0-1

oak chasm
#

Then we get:```
0100

  • 1000
    1100```with a borrow.
#

So, you borrow 1 from the integer part.

#

You get 1111 for the integer part and then you add that borrowed 1 in to the top of the fractional part to get 0100.

#

So, you get 1111.0100

#

Which is -1.25.

#

So, let's check that.

#

8.25 - 8.5 = -0.25

#

Hmm.

clever mountain
#

is this channel open now?

alpine sable
#

okay

#

so

#

30/100 x 60/1 = 1800/100 = 180 = ?

#

need help

oak chasm
#

@alpine sable Sorry, this channel is busy.

alpine sable
#

oh sorry

#

ill move on.

oak chasm
#

8.25 - -8.5 = 16.75

#

Forgot that we were subtracting a negative.

#

Looks like you have to check the sign of what you're subtracting.

#

If it's negative, you add the fractional parts. If it's positive, you subtract the fractional parts.

#

So, we should have added:```
0100

  • 1000
    1100
#

So, we get 0000.1100 = 0.75.

#

And 8.25 - -8.5 = 16.75, which has an overflow, so you subtract the 16.

#

8.25 - -8.5 - 16 = 0.75

alpine sable
oak chasm
#

@unborn sleet Does that make sense?

#

You have to look at the integer part's sign to tell whether to add or subtract the fractional part.

unborn sleet
#

Give me two numbers and I’ll try

oak chasm
#

OK, 13.75 - -4.5.

#

Should get 18.25 - 16 = 2.25

unborn sleet
#

So I’ll have to add the fractional part

#

If I understood

#

For the integer part I add

#

If I get a negative I subtract the fractional part

#

If I get a positive I add the fractional part

oak chasm
#

You have (13.75) - (-4.5).

#

So, you need to subtract the integer parts.

#

Then, you need to use the sign of the original second integer part to tell you whether to add or subtract the second fractional part.

#

A less complicated way might be to convert the numbers to the reasonable way to do it and back.

unborn sleet
#

Ok, 13.75 = 01101.11000

#

-4.5= 11100.10000

#

I subtract
01101
11100

#

I do not know how to subtract 1 from 0

oak chasm
#

Borrow.

unborn sleet
#

Where do I borrow it, there isn’t the bit sign equal to 0 repeated?

oak chasm
#

From the next more significant bit.

unborn sleet
#

Would it not be zero?

oak chasm
#
  01101
- 11100
   0001
unborn sleet
#

Yeah I’m locked here

oak chasm
#

You treat it as if the next digit on the top number is 1.

#
 101101
- 11100
   0001
unborn sleet
#

I did not know that

oak chasm
#

2 - 1 is 1, so:```
101101

  • 11100
    10001
#

Well, you only have five bits to work with.

#

And then the bits beyond that do not matter. They can be anything.

#

So, you make them something that will work.

unborn sleet
#

Perfect

#

So I get 11110001

oak chasm
#

So, now you check the negative/nonnegative bit of the second integer part.

#

11100.

#

It's 1, so it's negative instead of nonnegative.

#

And that means you add instead of subtract the fractional parts.

alpine sable
#

this is not a troll question

oak chasm
#

@alpine sable Sorry, this channel is busy.

alpine sable
#

alr

unborn sleet
#

You are great

#

We said that if we had to borrow for the fractional part we would do it front the integer part?

oak chasm
#

Yes.

#

You subtract 1 from the integer part and use it in the fractional part.

#

Similarly, if the fractional part overflows the other way, you add 1 to the integer part.

unborn sleet
#

I would do it from the result we got from the subtraction of the integers?

oak chasm
#

Yes.

unborn sleet
#

Thank you so much

#

Do you have a pathreon or something?

oak chasm
#

No, not really.

raven rover
#

People aren't really supposed to ask for money/pay for this kinda help

#

But that's pretty cool

#

If money were to get involved I imagine it should be in DMs or something, not here.

unborn sleet
#

Dude this man is great

oak chasm
#

I can't really accept payment.

unborn sleet
#

It’s just a little appreciation for the amazing job

#

He gave me so much time and cleared all my doumbts

raven rover
#

Yeah - people here are really good at that

#

I don't understand it

unborn sleet
#

I’ll write down what he taught me for sure ahah

raven rover
#

You can probably ask him/her what you can do to pay them back, although I imagine it'll just be along the lines of

Be nice.
Help others when you can to return the favor.

etc.

#

Or, it may be nothing at all

unborn sleet
#

I’ll return the favour for sure when I can

plush stump
#

x = 4 for #7 right?

drifting wadi
#

you can arcsin(3/5) to find x

#

but make sure u use the angle in the second quadrant

#

so type π-arcsin(3/5) to find x

#

in calc

oak chasm
#

You can use the Pythagorean identity to get cos(x), remembering you're in the second quadrant for the sign of it.

#

Then, you have sin(x) and cos(x), and can get tan(x).

plush stump
#

cos(x) = 4/5

oak chasm
#

Yes, and tangent?

plush stump
#

1sec

#

12/25

oak chasm
#

Nope, tan(x) = sin(x)/cos(x).

plush stump
#

lemme reduce

#

that's what I did

#

3/5 / 4/5 right

ocean sealBOT
#

Chai T. Rex

oak chasm
#

Dividing fractions is multiplying by the reciprocal of the bottom.

plush stump
#

oh yes, forgot to flip the bottom

#

15/20 then

oak chasm
#

Which reduces to what?

plush stump
#

3/4

oak chasm
#

OK, one small mistake. You're in the second quadrant, so cosine and tangent are what signs?

plush stump
#

cosine and tangent are negative

oak chasm
#

OK, so cos(x) = -4/5 and tan(x) = -3/4

#

And then you're done.

plush stump
#

but is x in the set tho

oak chasm
#

x is the angle. You only need it to tell you what quadrant it's in.

plush stump
#

OH

oak chasm
#

The angle is between π/2 and π, which is the second quadrant.

plush stump
#

nice nice, this one example online that said "verified" used the angle x and x/r as the same thing?

oak chasm
#

I'm not sure what they did.

plush stump
#

yeah well, they solved it oddly, and it was probably wrong

#

Thanks a lot! let me just solve 8 and get back to you on that

oak chasm
#

You're welcome. OK.

unborn sleet
#

If I borrow I give it to the MSB?

#

Of the fractional

#

Or do I have to do multiple borrows

oak chasm
#

Yes, you take from the least significant bit of the integer part and put that as an extra 1 digit in front of the fractional part.

unborn sleet
#

It’s like I add one bit

#

Great

#

I thought I had to do multiple borrows and subtract each time one, but it seemed strange since I could not do the same for the overflow

#

Since I could add only one bit

#

The overflow verifies only if I have 1+1 for the MSB of the fractional?

#

Or 1+1+1?

oak chasm
#

I'm not sure what you mean.

#

You'll only have to borrow zero or one times from the integer part.

plush stump
oak chasm
#

Almost.

#

cos²(x) = 1/5.

#

So, cos(x) = sqrt(1)/sqrt(5).

plush stump
#

ah yes you're right

oak chasm
#

And then you can use the Pythagorean identity again to get sin(x).

#

Then you give them signs based on which quadrant you're in.

#

The interval x is in is the first and second quadrants and the tangent is positive, so which quadrant are you in?

oak chasm
plush stump
#

[0, pi/2] is the first quadrant right? so All are positive

oak chasm
#

Yes.

plush stump
#

so full answers are tan(x) = 2, cos(x) = 1/sqrt(5), sin(x) = 2/sqrt(5)

oak chasm
#

Good, now does your teacher want square roots on top of fractions only or is that OK with them?

plush stump
#

honestly not sure.

oak chasm
#

Oh, then if you hadn't heard that they wanted that, you should be fine.

plush stump
#

Thanks for the help once again!

oak chasm
#

You're welcome.

tight locust
#

if you select two random points in the unit square

#

and make a line between them

#

and repeat that process an arbitrary number of times

#

what will the mean of all those lengths be

#

^ a question posed to me by my math teacher

#

i'm not sure how to go about it

#

should i code it?

charred flint
#

is it a line on the sphere or through it

oak chasm
#

You could, but that would only give you an approximate answer, not the reason why it's true.

charred flint
#

one question is easier than the other

tight locust
charred flint
#

oops I misread that as sphere aaa

#

what class are you in?

tight locust
oak chasm
#

Right, so you'd lose that as well.

#

Unless it happened to be an easily noticeable value.

tight locust
#

so idk how to go about it. i think an approximate answer would be good enough right?

#

honestly if i could just figure out how to code it that would probably be good enough

#

it's just for fun anyways

oak chasm
#

Well, you could use the Pythagorean theorem.

#

It has (x₁ - x₂)² for the x component of the distance. What would the expected value of that be?

charred flint
#

oh nvm I remember this problem, go and code it instead lmao

clever mountain
#

so it's a cube? and the lines are in it?

oak chasm
#

No, it's a closed square that contains the lines.

clever mountain
#

oh so it's just a 2d square?

oak chasm
#

Any point in the closed square to any point in the closed square.

#

Right.

#

And it's a unit square.

#

So, what's the expected value of the length of a random line in the square?

clever mountain
#

how many lines inside of it? as many until the number stabilizes?

oak chasm
#

Well, it will stabilize at the expected value, so you really only need one line.

clever mountain
#

right but then if you add another the value will change

tight locust
oak chasm
#

Well, let's get an expected value for the absolute difference in x coordinates.

#

Then the absolute difference of the y coordinates will be the same.

#

So, you'll have sqrt(2 d²) or whatever.

charred flint
#

I don't think doing x and y separately works x_x

oak chasm
#

They're independent, though.

#

You may be right.

charred flint
#

yeah the square root of expected values makes it break

tight locust
#

So i was thinking

#

Maybe just use a random value generator

#

In the interval [0,1]

#

And then do that again

#

And then Pythagorean theorem it

#

For like 1000 iterations

clever mountain
#
import random
import time

import pygame
import math

run = True

white = (255, 255, 255)
black = (0, 0, 0)

width = 1000
height = 900


def length(v_1, v_2, distance_to_surface):
    value = 0
    for x in range(len(v_1)):
        value += math.pow(v_2[x] - v_1[x], 2)
    return math.sqrt(value) - distance_to_surface


def change_pos(pos, keys_pressed_var):
    speed = 3
    speed_count = 0
    if keys_pressed_var[pygame.K_w]:
        speed_count += 1
    if keys_pressed_var[pygame.K_a]:
        speed_count += 1
    if keys_pressed_var[pygame.K_s]:
        speed_count += 1
    if keys_pressed_var[pygame.K_d]:
        speed_count += 1

    if speed_count == 0:
        pass
    elif speed_count > 1:
        speed = speed / 2

    if keys_pressed_var[pygame.K_w]:
        pos = (pos[0], pos[1] - speed)
    if keys_pressed_var[pygame.K_a]:
        pos = (pos[0] - speed, pos[1])
    if keys_pressed_var[pygame.K_s]:
        pos = (pos[0], pos[1] + speed)
    if keys_pressed_var[pygame.K_d]:
        pos = (pos[0] + speed, pos[1])
    return pos


window = pygame.display.set_mode((width, height))
pygame.display.set_caption("Boids")

fps = 120
clock = pygame.time.Clock()

while run:
    for this_event in pygame.event.get():
        if this_event.type == pygame.QUIT:
            run = False

    clock.tick(fps)

    window.fill(white)

    pygame.draw.rect(window, (0, 0, 0), (100, 100, 700, 700))

    average = 0

    for i in range(10000):
        coord_start = (random.randint(100, 800), random.randint(100, 800))
        coord_end = (random.randint(100, 800), random.randint(100, 800))
        point = length(coord_start, coord_end, 0)
        average += point
        pygame.draw.line(window, (0, 255, 0), coord_start, coord_end)
    average = average / 10000
    print(average)

    pygame.display.update()
    time.sleep(1000)
pygame.quit()
unborn sleet
#

@oak chasm I found an error in the process
+4.25 = 0100.0100
-4.25 = 1100.0100

Subtracting the integer parto

0100
1100

subtracting the fractional part

0100
0100

0000

The result is 1000.0000 instead of 0000.0000

clever mountain
#

this was the average length

365.0328661311797
#

in pixels in a square that's 800 pixels wide

tight locust
#

,calc 365.032866/800

ocean sealBOT
#

Result:

0.4562910825
tight locust
#

How many iterations?

clever mountain
#

1 million iterations

365.63005509551624
#

which completely filled in the black square

tight locust
#

,calc sqrt(1/2)

ocean sealBOT
#

Result:

0.70710678118655
tight locust
#

Wow lol

#

Where does that number come from

clever mountain
#

lol

tight locust
#

,w 0.4562910825

oak chasm
#

And since you're subtracting a negative, you add the fractional parts to get 1000. So, 8.5.

unborn sleet
#

We did not say if the second integer had a 1 we would subtract the fractional parts?

#

since id like to get zero i would have to do 4.25 + (-4.25) ?

oak chasm
#

The second integer was 1100.

#

So, for the fractional parts, you add them.

unborn sleet
#

sorry

#

i did not understand the part 4 --

#

so we add if the number is negative and subtract if it is positive

#

+4.25 = 0100.0100
-4.25 = 1100.0100
tto get zero

Add the integer parts

0100
1100

#

but we would not have to subtract the fractional parts

#

?

#

also if the second integer has 1

sick torrent
#

Why is this wrong?

dry echo
clever mountain
clever mountain
dry echo
#

How did you end up with 10 on the numerator? @sick torrent

#

4 * 5 = 20 not 10

tight locust
clever mountain
#

for the record the length would have been

0.456625

of the length of the square

unborn sleet
#

So for a - (b) I subtract the integer parts, if the b has 1 as MSB I add the fractional parts if it has 0 I subtract them, for a + (b) I add the integer parts if b has 1 as MSB I subtract the fractional parts if it has 0 I add them @oak chasm

late parcel
#

Couldn’t x=-1 or x=4 be it?

#

Because an absolute can also be considered a local

daring schooner
buoyant kayak
late parcel
#

Yes

buoyant kayak
#

not f

late parcel
#

I’m confused

#

So then how do you tell

buoyant kayak
#

you’re asked about the max of the function f given the graph of f’

#

when do you meet a maximum, in terms of the derivative?

late parcel
#

At the top

buoyant kayak
#

?

late parcel
#

Idk

buoyant kayak
#

what is the value of the derivative when you’re at a maximum or minimum

late parcel
#

The greatest

buoyant kayak
#

i’m talking about the derivative

#

you’re talking about the function

late parcel
#

I don’t know

buoyant kayak
#

the function is at a maximum, sure. but it’s derivative?

late parcel
#

I don’t know what the difference is

buoyant kayak
#

between the function and the dericative?

late parcel
#

The first derivatives gives you the min and max

buoyant kayak
#

what do you do to find the min and max?

#

take the derivative and…?

#

do what?

late parcel
#

Do the first derivative test

#

Find critical points

#

Check if it’s increasing or decreasing

buoyant kayak
#

what do you set the derivative equal to?

late parcel
#

Set it equal to zero

buoyant kayak
#

right

#

so you’re finding where the derivative in zero

#

that’s where your mins and maxes are

#

so look back at your graph of f’

#

when is there a min or max?

late parcel
#

I’m so lost it’s not even funny

#

I still have absolutely no idea if it’s not -1 or 4

#

@buoyant kayak can you tell me what it is and I’ll see if it makes sense

tight locust
#

What ide/language

buoyant kayak
late parcel
#

Yes

buoyant kayak
#

so when you solve for that, it tells you the x values that the derivative is equal to zero

#

you’re given a graph of the derivative of f.

#

when does the function f have a min or a max? when this graph is what?

strong vapor
#

Is this correct? It’s a warm up acivity

buoyant kayak
#

channel taken

late parcel
#

@strong vapor not open

coral pagoda
clever mountain
tight locust
#

What ide

clever mountain
#

pycharm

late parcel
#

Is it 1

strong vapor
#

How about this one?

late parcel
#

Is it 1

#

Or wait no

#

Idk honestly

tight locust
buoyant kayak
late parcel
#

How

#

I just guessed

buoyant kayak
#

what is true at x=1

#

on your graph f’

late parcel
#

It has a Y value of 0

buoyant kayak
#

so it’s equal to zero

coral pagoda
#

Oh. You're helping someone, not the other way around 🤦‍♂️

late parcel
#

What is equal to 0

#

Bro

buoyant kayak
#

which makes it a critical point, correct? when the derivative is equal to zero?

late parcel
#

How

#

No

strong vapor
#

This warm up activity is annoying

sudden crow
#

please i need help (lesson continuity)

strong vapor
late parcel
#

@strong vapor @sudden crow not open

#

Please stop

#

@buoyant kayak x is not 0 at 1

#

Please walk me through it again

#

I mean how can you find a critical point when your not even given the function

#

Or equation of the derivative

#

@buoyant kayak see number 12?

alpine sable
#

please help

late parcel
#

I did the first derivative test

#

And I graphed the first derivative ok the right their

#

That graph tells me that f has a local min at x=3

#

Right @buoyant kayak

buoyant kayak
#

that’s not what the graph of f’ looks like

alpine sable
#

im gonna get beaten by my dad

buoyant kayak
#

your derivative is gonna be a quadratic

alpine sable
#

cause of a literal iready

late parcel
#

@alpine sable please go to another channel

alpine sable
#

can someone just

#

okay.

late parcel
#

@buoyant kayak yes I know that

#

But still I graphed the derivative

#

The first derivative gives you the min and max

#

Well look at this question

#

It gives you the derivative of f

#

So why is it not -1 or 4

buoyant kayak
#

because you’re not trying to find the mins and maxes of the derivative

#

you’re finding the mins and maxes of the function f

#

not f’

late parcel
#

Ok so please walk me through it again

#

I have the graph

buoyant kayak
#

of f’

late parcel
#

I have no equation to set equal to zero

buoyant kayak
#

you don’t need one

#

how do you find the mins and maxes of f?

late parcel
#

Set the derivative equal to zero

buoyant kayak
#

so finding when the derivative is zero

late parcel
#

I only have a graph

late parcel
buoyant kayak
late parcel
#

Ok

#

How do you do that on a graph

buoyant kayak
#

when you set the derivative equal to zero, you solve for x, you’re finding the x values where the derivative is equal to zero

late parcel
#

Yes

buoyant kayak
#

you have the graph of the derivative of f

late parcel
#

Yes

buoyant kayak
#

so… when is the derivative equal to zero

late parcel
#

How do you tell when it equals zero on a graph

buoyant kayak
#

?

late parcel
#

No stopping points

#

Only sharp turns

buoyant kayak
#

you’re not finding when the slope of your graph is zero

#

you’re finding where your graph is zero

#

the graph IS the derivative

late parcel
#

The derivative does not equal zero in this graph

buoyant kayak
#

the graph is the derivative

late parcel
#

The Y value happens to be 1 at x=0

buoyant kayak
#

so the slope of f at x=0 is 1

late parcel
#

But the question is what is the x

#

How

#

How do you see that

buoyant kayak
late parcel
#

Is that because of the Y value

buoyant kayak
#

yes

late parcel
#

Is the Y value relevant

#

Why

#

Why would you look at the Y value

buoyant kayak
#

…because it’s a graph of the derivative

late parcel
#

The question asks for an X value

buoyant kayak
#

the y value is the slope at a point x

late parcel
#

No

#

How is the Y value a slope

#

The Y value is the value the graph is al vertically

buoyant kayak
#

how do you find the slope of a tangent line?

late parcel
#

Umm I’m blanking

buoyant kayak
#

if i gave you the function f(x)=x^2, what is the slope of the tangent line at x=2?

late parcel
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4

buoyant kayak
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and you did that how?

late parcel
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2^2

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=4

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Plug and chug

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I remember now

buoyant kayak
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you took the derivative and plugged in a point x

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and the value of the derivative at that point is f(x)

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which is the slope of the line

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at that point

late parcel
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Yes

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How is this relevant

buoyant kayak
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so… what is f’(1) in your shown graph

late parcel
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0

buoyant kayak
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so the slope is zero at x=1

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and when the slope is zero… you’re at a critical point

late parcel
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Is that it

buoyant kayak
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that’s f(0)

late parcel
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Or that

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Which one is why

buoyant kayak
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the one where f’(x)=0

late parcel
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The second?

buoyant kayak
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yes

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where the derivative is equal to zero

late parcel
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Ok thx

buoyant kayak
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and you’re going from a positive slope to a negative slope

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therefore it’s a maximum

late parcel
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Thx

near falcon
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how do i solve the area of a sector

late parcel
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@buoyant kayak wait

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What

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That’s double negative slope

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Oh wait never mind