#precalculus

1 messages · Page 215 of 1

maiden igloo
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okay let me write it out

steel venture
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prefect

maiden igloo
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Like that ?

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Excuse my hand writing

steel venture
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awesome

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ok do you know logarithms

maiden igloo
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a little

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i know

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logging it

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removes the

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variable from the exponent

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like pulls it down ?

steel venture
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sort of

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but thats not what we're looking for here

maiden igloo
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aight

fleet yew
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you can simplify that a lot

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(a^b)^c = a^(bc)

daring yarrow
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u dont need logs to solve this do you?

maiden igloo
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i don't think so

daring yarrow
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just equal exponent rule thing

maiden igloo
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Now that we have it equal the same base

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do i do

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...

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lost

sour inlet
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i'm completely lost maximo, still can't figure out

fleet yew
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$(2^2)^{x^2} = 2^{2x^2}$

obsidian monolithBOT
maiden igloo
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uh

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okay

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so that's how it should be written

fleet yew
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uh huh

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then you have

maiden igloo
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got it

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\

fleet yew
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$2^{2x^2} \times 2^{5x} = 2^{3}$

obsidian monolithBOT
maiden igloo
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why did we switch it

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from the 8 being on the left side

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?

fleet yew
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doesn't matter lol

maiden igloo
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ahh so it's your preference ?

fleet yew
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yeah sure

maiden igloo
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aight

fleet yew
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now what can you do

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if you have 2^a times 2^b

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how do you simplify that

maiden igloo
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2a * 2b

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that would

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4ab

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?

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wait no

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wait yes

fleet yew
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no

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let me give you an example using real numbers

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what is 2^2 * 2^3

maiden igloo
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oh

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4 * 8

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= 32

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?

fleet yew
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and what is 32?

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in terms of powers of 2?

maiden igloo
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and even num

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um

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it is a ....

fleet yew
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32 = 2^5

maiden igloo
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oh

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okay

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make sense

fleet yew
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and 5 = 3 + 2

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so we can just add the exponents together

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and put it over the same base

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2^2 * 2^3 = 2^5

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see

maiden igloo
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care to throw up that wonderful text

fleet yew
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let's just look at the left hand side of the equation now.

maiden igloo
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yeah

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starting from 8

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🙂

fleet yew
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$2^{2x^2} \times 2^{5x} $

obsidian monolithBOT
maiden igloo
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wait okay

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i see

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okay so starting from here

fleet yew
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$ = 2^{2x^2+5x}$

obsidian monolithBOT
fleet yew
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because you add the exponents together

maiden igloo
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ahh we can combine

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okay

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and we can do this because we share the same base

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is that correct

fleet yew
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yes

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and now

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$ 2^3= 2^{2x^2+5x}$

obsidian monolithBOT
maiden igloo
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now

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we

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multiply

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2 by the whole exponent

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?

tardy ridge
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the bases are the same

maiden igloo
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oh

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so can i set to zero

tardy ridge
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so if 2^5=2^x what is x

maiden igloo
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0 = 2^2x2+5x - 2^3

tardy ridge
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(that x has nothing to do with the question just an example)

maiden igloo
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oh rop

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rip

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um

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do i just solve now

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2x^2+5x ?

tardy ridge
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$ 2^5=2^x$

obsidian monolithBOT
tardy ridge
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what is x

maiden igloo
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5

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?

tardy ridge
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YES

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!!

maiden igloo
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im laughing

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oh man im so dumb

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okay

tardy ridge
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you have

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$ 2^3= 2^{2x^2+5x}$

obsidian monolithBOT
tardy ridge
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so what is 3 equal to

maiden igloo
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8

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wait

tardy ridge
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lol

maiden igloo
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😦 lost me

tardy ridge
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ok so

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$2^x=2^n$

obsidian monolithBOT
tardy ridge
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what is x in respect to n

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infact we can do this

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$b^x=b^n$

obsidian monolithBOT
maiden igloo
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x=n

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?

fleet yew
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yes

tardy ridge
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YES!!

fleet yew
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but only over the reals

daring yarrow
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cmon amd

tardy ridge
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so if you try that with your equation

maiden igloo
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x = 3

daring yarrow
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no nono

tardy ridge
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no he's comparing to orginal equation

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let's see what he makes n equal to

daring yarrow
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oh

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yesyesyes

tardy ridge
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that's what I think s/he is doing anyway

maiden igloo
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based on the examples you gave me I am assuming whatver my x is on one side it's reflected on the other

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but i feel like that isn't right

tardy ridge
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x and n are variables in my equation

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they can represent a whole expression=

daring yarrow
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$b^(n)=b^(5+2)$

obsidian monolithBOT
daring yarrow
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wtf

tardy ridge
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piece what

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lmao

daring yarrow
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idk how this bot works

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wanted to look smart

tardy ridge
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I think you use the swiggly one

daring yarrow
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eh just nvm me i'll lurk

tardy ridge
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ok it might be easier to explain if you use log, do you know what log is @maiden igloo ?

daring yarrow
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2^(x²+2x+1) = 2^-1

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idk if this example could help but this is what got one of my friends to understand how it works

unique hill
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$2^{x²+2x+1} = 2^{-1}$

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there

tardy ridge
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good job

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that -1 part

daring yarrow
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still messed up GWmythicalFeelsSadMan

obsidian monolithBOT
tardy ridge
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wait what happens if I react to it

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o

daring yarrow
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and you know that
$b^n=b^x$

obsidian monolithBOT
daring yarrow
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when n=x

tardy ridge
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I think subi is long gone

daring yarrow
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rip

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this selfstudy stuff is pretty tough sometimes

maiden igloo
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Nah i am

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here

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gf stepped in and helped

tardy ridge
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do you know what log is

maiden igloo
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i do know

tardy ridge
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just log 2 both sides

maiden igloo
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but i probably not sure how to use correctly

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I got the answer

tardy ridge
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nice

maiden igloo
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I realized that

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it was

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3 2x^2+5x

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I kept thinking we had to do something with the bases

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so i got confused

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But i understand now that the example you showed me

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$2^x=2^n$

obsidian monolithBOT
maiden igloo
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is saying

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x = n

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which are my exponent values

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so set

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x = n whatever that is and in my case was

tardy ridge
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yes

maiden igloo
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$ 2^3= 2^{2x^2+5x}$

tardy ridge
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so what's the answer you got

obsidian monolithBOT
maiden igloo
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-3 , 1/2

daring yarrow
tardy ridge
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nice

daring yarrow
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goodjob

maiden igloo
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but dinner timw

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ill be back

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i appreciate you guys

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a lot

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im trying to get better

tardy ridge
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wait

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one thing

daring yarrow
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dont give up and you'll be fine

tardy ridge
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if the bases are different but they can turn into the same you can do that

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like 4^x = 2^2x

daring yarrow
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$4^x=2^{2x}$

obsidian monolithBOT
daring yarrow
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ezPeepoHappy

tardy ridge
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ok piece do want to try a problem relating to this? It's not too difficult but I'll just put this here cause i came up with it like a minute ago

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$b^{2k}=(-b)^{k^2+1}$

obsidian monolithBOT
daring yarrow
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its 4am so cant guarantee ill be able to solve

tardy ridge
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logs aren't gonna work now

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wth

daring yarrow
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lemme get up and grab a piece of paper

unique hill
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you gonna solve for k or b?

daring yarrow
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k

unique hill
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2 unknowns

tardy ridge
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k because b can be anything

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yes that's true

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but piece you should go to sleep

daring yarrow
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what are the solutions

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@tardy ridge

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ima just say there arent any

tardy ridge
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if k^2+1 is even then there is

daring yarrow
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i tried squaring both sides but idk

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@tardy ridge how many solutions?

tardy ridge
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2

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k=1 and k=s1

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-1

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look if k^2+1 is even then -b doesn't matter

daring yarrow
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figured but idk how to get there without just thinking

tardy ridge
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if you square (-2)^even then it's 2^even

daring yarrow
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can u actually calculate this

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or is it just thinking

unique hill
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but you dont know if it's odd or even

tardy ridge
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@unique hill if k^2+1 is even, k=1 k=-1 but -1 doesn't work so k=1

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and k^2+1 is indeed even because 1+1 is even

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the equation basically becomes b^2=(-b)^2

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when k=1

maiden igloo
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I have two more question , the first one I just wanna confirm if im understanding the problem correctly

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which is this

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Information is given about a polynomial f whose coefficients are real numbers.
Find the remaining zeros of f .
Degree 5; zeros: -4, i, 5 − 3i

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I said the remaining zeroes were -4 , i ,-i , 5-3i , 5+3i

cedar pawn
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Can u send a picture

maiden igloo
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Yes sir

cedar pawn
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Oki

maiden igloo
maiden furnace
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how do i get the period of this?

uncut mulch
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don't need to list all 5

maiden igloo
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you talking to me

uncut mulch
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the remaining (2) zeroes in Q11 would just be the:
-i and 5 + 3i

unique hill
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he's doing prev question

maiden igloo
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Okay so i figured it was those for question 11

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it just seem so simple

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so thought it was wong

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wrong*

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I got 12 btw

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the demon question

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I skipped cause I was struggling is this one

uncut mulch
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that info layout is horrid

maiden igloo
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THANK YOU

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do you see the lonely i

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in the corner

uncut mulch
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3 is a zero with multiplicity of 2
i is also a zero

cedar pawn
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(2+i)2

maiden igloo
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but why is I not listed with the zeroes

cedar pawn
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(2+i)^2

maiden igloo
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i thought it would be

cedar pawn
maiden igloo
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(x-3)^2

uncut mulch
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they separated the list with ;

cedar pawn
maiden igloo
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Can someone walk me through or point me to resources to explain this better

cedar pawn
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Khan academy

uncut mulch
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it uses the idea as the previous questions

maiden igloo
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The degree should reflect the amount of zeroes ... is this correct

uncut mulch
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conjugate root theorem

maiden igloo
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gotta look that up

fleet yew
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if a+bi is a root, then a-bi is a root, assuming the polynomial has real coefficients

uncut mulch
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its pretty much exactly the same thing as what you just applied

fleet yew
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because (a+bi)(a-bi) = a^2 + b^2 so it must have the conjugate so the imaginary parts can cancel out

unique hill
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i see the word imaginary...

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is this precalculus?

fleet yew
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yeah

unique hill
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wait im pretty sure complex numbers are not precalculus

cedar pawn
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Ain't it prealgebra

unique hill
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for my curriculum, calculus is taught before complex numbers

maiden igloo
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Complex nums is College algebra

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But I don’t recall these theorems

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I’ll openly admit I didn’t try as hard as I should have in the past and I’m obviously paying for it now , but I’m willing to go through that now

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Cause I need this to be where I wanna be

unique hill
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i havent touched on complex numbers

maiden igloo
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What math are you in

unique hill
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as in?

maiden igloo
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so

fleet yew
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complex numbers are like algebra 1 wtf

maiden igloo
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chill man

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take it easy on us

fleet yew
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like how else do you solve x^2+1=0

maiden igloo
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uh

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oh

fleet yew
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no i'm just saying how do you do calculus without knowing what i is

maiden igloo
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x^2 = -1

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oh square root of negative

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give ...

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i know it's like i or something

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i think

fleet yew
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+-i

maiden igloo
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So

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I am confused how conjugate root theorem is used here

unique hill
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there's no theorem

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it's like x^2=1

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x=+-1

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but with i

fleet yew
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conjugate root theorem says

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if $(x - (a + bi))$ is a root of a polynomial with real coefficients, then $(x - (a - bi))$ must also be a root of the polynomial

obsidian monolithBOT
unique hill
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@fleet yew in response to ur comment, ik what i is but havent done anything with it

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all ik is 1/i = -i

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and stuff i did in calculus has no use of complex numbers

willow bear
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@fleet yew factor not root

maiden igloo
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I am referring to my question

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I thought Degrees were connected to the zeros

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for exmaple

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Degree 3

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zeroes 1, 2 , 1+i

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sorry

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Degree 4 zeroes 1, 2,1+i

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i would assume it's the conjugate paiur

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pair*

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But here

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the Degree is 3

patent beacon
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If you count multiplicity, then there's exactly as many zeroes as the degree

maiden igloo
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Hmm

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First time dealing with mulitplicity in this regard

harsh cipher
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Good morning Ann

maiden igloo
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I am aware of it for determining if

patent beacon
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If the polynomial has real coefficients, then 1-i is a root as well

maiden igloo
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it cross x or bounces

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So confused 😭

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so

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is x-3 not a zero here ?

patent beacon
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Oh, but you said it's degree 3. So, the polynomial must not have real coefficients

maiden igloo
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Here

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Form a polynomial f (x) with real coefficients having the given degree and zeros. Show your work! Degree 4; zeros: 3, multiplicity 2; i

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Oooooooo

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wth

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I kept reading it like this

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Degree: 4
Zeroes:3
Multiplicity:2

i

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So multiplicity is apart of the zeroes

patent beacon
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A zero also has a multiplicity, yeah

maiden igloo
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is i not apart of the zero ?

harsh cipher
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question

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(2)^1-x = (5)^x

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solve exactly for x then evaluate your solution rounding to 3 decimals

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why cant I log both sides and perform simple algebra?

steel venture
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before anything

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is it

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(2)^(1-x) = (5)^x

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or

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(2)^(1) - x = (5)^x

harsh cipher
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opps

steel venture
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i.e. $2^{1-x}=5^x$

obsidian monolithBOT
harsh cipher
#

its that one

steel venture
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ok

harsh cipher
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I forgot parentheses

steel venture
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they aren't the same base

harsh cipher
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i hope Ann is not watching

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yes they are not

steel venture
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lmfao

harsh cipher
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so I need to log both sides

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hahahaha

steel venture
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the problem is you can't because theyre not the same base

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what can be done though is using one of the log rules

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$log(a^b)=blog(a)

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$log(a^b)=blog(a)#

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$log(a^b)=blog(a)
$

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fuck

obsidian monolithBOT
harsh cipher
#

power rule?

steel venture
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yep

harsh cipher
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okay

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do I apply the power rule to both sides of the equation?

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I just solved the previous problem

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using the same rule

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(3)^(2x+5) = 54

steel venture
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54 = 3*18

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so you can use log base 3

harsh cipher
#

I did it different way

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(log 54 )/ (log3) = 2x+5

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also that did not make sense when you said 3*18

steel venture
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ok well its applicable to both problems i think

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wait it didn't make sense

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why

harsh cipher
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because 3^(2x+5)= 3*18

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basically what you're telling me is that

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I can equate (2x+5) to 18?

steel venture
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no

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what i was implying

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is that you can log base 3 to get

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$2x+5=1 + log_3(18)$

obsidian monolithBOT
fleet yew
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RHS simplifies to 3 + log_3(2)

steel venture
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oh

willow bear
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\log

steel venture
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thanks ann

harsh cipher
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oh hi there

steel venture
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ill remember for next time

maiden igloo
#

last question before i go to bed. Dealing with these real world problems as such , I get confused with what data goes where

#

Between 12:00 PM and 1:00 PM, cars arrive at a bank’s drive-thru at the rate of 12 cars per hour (0.2 car per minute). The following formula from statistics can be used to determine the probability that a car will arrive within t minutes of 12:00 PM.

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F (t) = 1 − e −0.2t

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Determine the probability that a car will arrive within 10 minutes of 12:00 PM. Round to two decimal places as needed.

harsh cipher
#

I can be patient let's help subi first

fleet yew
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No lets finish your question

harsh cipher
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okay sure

maiden igloo
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no

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finish your stuff first

harsh cipher
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okay thank you

viscid thistle
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is e the constant?

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or variable

harsh cipher
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so my question (2)^(1-x) = (5)^(x)

viscid thistle
#

@maiden igloo

maiden igloo
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yeah it is

viscid thistle
#

oh constant

maiden igloo
#

I believe this is an expotential growth function

viscid thistle
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yes

maiden igloo
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i always get them confused

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between

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decay

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growth

willow bear
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(2)^(1-x) = (5)^(x)
three of these four pairs of parentheses are redundant thonk

steel venture
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ann you're very nitpicky haha

viscid thistle
#

is it not simply F(10)? @maiden igloo

maiden igloo
#

uh

viscid thistle
#

oh

maiden igloo
#

Idk

viscid thistle
#

within

maiden igloo
#

I am trying to understand how to break this down

steel venture
#

mirrion go to a questions channel ill help you

viscid thistle
#

hmm

harsh cipher
#

which channel

fleet yew
steel venture
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any one not occupied

harsh cipher
#

okay thank you see you there

maiden igloo
#

do i put 10 in for F(T)

viscid thistle
#

It would be negative

maiden igloo
#

and put 10 where t is

viscid thistle
#

No

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so 0.2 cars / min

maiden igloo
#

correct

viscid thistle
#

Are you sure F(t) is written correctly

maiden igloo
#

let me send pic

viscid thistle
#

ok

maiden igloo
viscid thistle
#

so thats

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different

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now please tell me

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i have never taken probability

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but its between 0 and 1?

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yes

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ok

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yes it should just be F(10)

maiden igloo
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okay

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So

viscid thistle
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but its saying within 10 mins

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yes

maiden igloo
#

1 - e^-0.2^10

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?

viscid thistle
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F(1)

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*F(10)

maiden igloo
#

let me work it out

viscid thistle
#

86.4%

distant rampart
#

How do you graph a 3d plane
Like
Its easy to plot the points by just finding intercepts

But i dont know how to draw the plane

steel venture
#

plot in what you need and copy it

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its your best bet

maiden igloo
#

i got the same

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@viscid thistle

distant rampart
#

Hmm i thanks
I tried that already i still couldnt get it
What im thinking of right now is just make up line equations in two dimensions then just somehow piece them together

viscid thistle
#

Alrigh

#

t

maiden igloo
#

Is there a way for me to donate to you guys

viscid thistle
#

Never donate

#

Just express thanks using English

maiden igloo
#

THANK YOU !

sour inlet
#

Guys I'm supposed to use a calculator to solve for theta on the interval [-90deg,90deg]
for Sin(theta) = 3/4

I did arcsin(.75) and got 48.5903 deg

unique hill
#

48.6 (rounded) degrees is one of the solution

sour inlet
#

and I also got 131.4096 deg from subtracting 48.6 from 180 deg

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since sin i positive in q2 right?

unique hill
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yep

sour inlet
#

but i don't understand what it means

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from a negative 90 deg

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to a positive 90 deg

unique hill
#

from a neg, you go clockwise along the ASTC circle

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so from 0 to 90 degrees, u go anticlockwise
but from 0 to -90 degrees, u go clockwise

sour inlet
#

One sec trying to process

maiden igloo
#

Good ole trig

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I have that class tomorrow

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Morning

sour inlet
#

what would that be

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-41.4 deg?

maiden igloo
#

+369

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360

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I think would give coterminal angle

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That is the same

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One of the smart guys can verify

unique hill
#

not +360

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x is between 90 and -90 degrees

maiden igloo
#

Rip so 90 ?

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90 + 41.6 ?

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41.4*

unique hill
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no 90+41.6 exceeds 90

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so it's not in the range of x

patent beacon
#

There's only one solution in that range, the one your calc gave you

sour inlet
#

hmm i see

maiden igloo
#

💀

#

Wait

sour inlet
#

thanks guys

maiden igloo
#

90 -41.4

unique hill
#

that's arcsin 3/4

maiden igloo
#

Would that be the coterminal

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Ahh okay I’m dumb

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Got it

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Thanks for all the help guys

#

I hope this discord is around for the next 2 years help me through college

#

Goodnight

sour inlet
#

gn

sour inlet
#

Last question for the day if anyone is still here

#

how would you go about getting the equivalent of 6sinxcos(5x)

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would it be

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3sin(6x)+3sin(4x)

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?

willow bear
#

"the equivalent"?

unique hill
#

are you talking about double angles?

sour inlet
#

that's all it asks

unique hill
#

ah

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do u know the product-to-sum formula?

willow bear
#

oh

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well

sour inlet
#

you mean like cos(a+b) = cosAcosB-sinAsinB

#

?

willow bear
#

no that's not what nightingale means

unique hill
#

that's not product to sum

#

those are compound angles

#

formula

willow bear
#

$\sin(a) \cos(b) = \frac12 (\sin(a+b) + \sin(a-b))$

obsidian monolithBOT
unique hill
#

thx for typing it in texit

sour inlet
#

oo

#

1/2(6sin(a+b) +sin (a - b))

#

what would a and b

#

be in this case?

unique hill
#

a and b are the respective angles

sour inlet
#

how would you get angles from something like this

#

doesn't look like I have much to work with, not much that i can see anyways

unique hill
#

first focus on the ones inside the brackets

#

ignore the 1/2 for now

#

so just $sin(a+b)+sin(a-b)$

sour inlet
#

sin(5x+x)

obsidian monolithBOT
sour inlet
#

?

unique hill
#

a and b are the matching angles

#

so compare them with $sinacosb$

obsidian monolithBOT
unique hill
#

my bad

#

with the question

sour inlet
#

all I can think of is
6sin(X+5X) + sin (X-5x)

6sin(6x) + sin(-4X)

unique hill
#

your working out is correct

#

but u might want to

sour inlet
#

6sin(6x) - sin(4X)?

unique hill
#

let a=5x and b=x

#

that's favourable bc you dont get a negative inside the bracket

sour inlet
#

ahhh

#

6sin(6x) + sin(4x)

#

then the 1/2?

unique hill
#

half it

#

remember the parenthesis

#

it's 6 times the WHOLE thing

sour inlet
#

6sin(6x)+6sin(4x)

#

1/2

#

3sin(6x) +3sin(4x)?

unique hill
#

minus in the middle

#

you're using a different formula now

#

becuz a and b are switched

sour inlet
#

o ok

#

so to avoid negative in bracket

#

formula was different and sign was switched

#

?

unique hill
#

$2cosAsinB=sin(A+B)-sin(A-B)$

#

uhh

#

why's there no parenthesis

sour inlet
#

where

#

o

obsidian monolithBOT
unique hill
#

no for my one

#

ok nice

sour inlet
#

and when did this fo rmula come into place

#

on the 1/2

#

?

unique hill
#

that is just 2 multiplied by the whole thing

#

ok now, u know that a=5x and b=x

#

you have everything u need to know

#

sub into $2cosAsinB=sin(A+B)-sin(A-B)$

obsidian monolithBOT
sour inlet
#

2(cos5X*sinX) = sin(5X+X) - sin(5X-X) ?

#

wait what happened to the 3

unique hill
#

yes and simplify

#

simplify first

sour inlet
#

2cos5XsinX=sin(6X)-sin(4x)

#

?

unique hill
#

yes

#

very good

#

wait

#

it's 2cos(5x)sinx for LHS

#

there's no extra 2

sour inlet
#

oh right cus we multiplied first in the paranthesis

unique hill
#

so now what's your LHS and RHS

sour inlet
#

2cos5XsinX
sin(6X)-sin(4x)

I'm not confused by the question, what do you mean what's on my left hand side and right hand side.

unique hill
#

there's an equal sign in between them

#

cuz you subbed in a and b into the formula which has an equal sign in the middle

#

so LHS=2cos(5x)sinx and RHS=sin(6x)-sin(4x)

sour inlet
#

right

unique hill
#

you follow me?

#

that eqn above

sour inlet
#

Well it's the first time I've seen something like that, but yes we have a LHS and RHS

#

and they're set to equal each other

unique hill
#

now what's the question asking?

sour inlet
#

Which of the sums is equivalent to 6sinxcos(5x)

#

my best guess would be 3sin(6x)-3sin(4x)

unique hill
#

yes that's correct

#

dont guess btw

sour inlet
#

but our RHS is completely different

#

ever since we dropped the 3 and moved onto a new formula

#

so i'm confused

unique hill
#

since u found out 2cos(5x)sinx, u can times 3 on the other side since the question is asking for 6cos(5x)sinx

sour inlet
#

ohhh

unique hill
#

so you times 3 for RHS

#

which makes 3sin(6x)-3sin(4x)

#

which should be correct

sour inlet
#

and lhs 6sinxcos(5x)

#

i see

unique hill
#

wait wha

#

no that's LHS

sour inlet
#

typo

unique hill
#

okok

sour inlet
#

thank you very much for your time and patience

#

appreciate it

unique hill
#

no worries

daring yarrow
#

lim(f(x)) = -inifinity
(x -->+inifnity)
i have to prove this using the epsilon gamma method but i uh

#

yeah i dont really get it

tardy ridge
#

What is the question

daring yarrow
#

wait nvm they're being as vague as ever in the book

#

just want me to write it in epsilon-delta form

#

aight then

maiden igloo
#

good morning

harsh cipher
#

good morning

sturdy haven
steel venture
#

,rotate

sturdy haven
#

Help with number four PLease

obsidian monolithBOT
sturdy haven
#

IM SO OCNGUSED

steel venture
#

try different points to see how it looks

sturdy haven
#

uhhh what

#

Thats not

#

I mean how do I space it out

#

And what intervals

#

And when use period

steel venture
#

ok the center is zero

#

and you have all that room on the right to get to 2 pi

#

so space it as you will but utilize the room wisely

sturdy haven
#

So i spaced it out an it is PI OVER FIVE

#

WHAT

#

ALSO THE PERIOD IS FOUR PI

#

what does that mean

#

how is im so confused right now

steel venture
#

ok

sturdy haven
#

because listen if spaced OUT evenly

steel venture
#

lets take it slow

sturdy haven
#

SO

#

ok

steel venture
#

count the lines to the right of the origin

#

vertical lines

sturdy haven
#

21

steel venture
#

ok

#

now you need to seperate that in 2

#

but oh no! its odd!

sturdy haven
#

o

steel venture
#

so move one back

#

and write 2pi

sturdy haven
#

what the

#

WHAT

steel venture
#

and then count 10 back

#

and write pi

sturdy haven
#

oh

#

wait what

#

so just leave EMpty space that tje end

steel venture
#

yes

#

no one is going to die from that

#

dw its safe

sturdy haven
#

I Wrote two pie now what

steel venture
#

move ten lines to the left

#

and write pi

sturdy haven
#

ok infucekd up

#

its only 20

#

so i wrote two pied at the end

#

And wrote pie in centrez

#

ok no waht

steel venture
#

then just earase and rewrite it

sturdy haven
#

i did

#

now what to do

steel venture
#

set the top of the graph to be equal to 1

#

and the bottom to -1

sturdy haven
#

ok

#

but whar if period is four PIE

steel venture
#

it doesn't matter

#

now all you have to do is plot points

sturdy haven
#

oh shet i fucked up

steel venture
#

until you can fill in the lines

sturdy haven
#

FREQUENCY IS ONE HAD

#

FUCK

#

the fricken frequency is one half!!!

steel venture
#

the period is 4 pi

#

you are correct

#

don't worry

sturdy haven
#

but the frequences

steel venture
#

the question didn't ask for that

#

all its asking is for you to plot the graph in the given interval haha

sturdy haven
#

now the whole grzphis is fucked up

#

the frequency is one hafe

steel venture
#

plot the point for theta=pi

#

and theta = 2pi

sturdy haven
#

i can’t

steel venture
#

and theta = pi/2

sturdy haven
#

ghe graph

#

ok

#

wait

#

so

#

for two pie

#

Is just cos pie

#

so

#

thats neg one

#

how on gods green earth do i do 3pie over Two

steel venture
#

unit circle

sturdy haven
#

no

#

its just one and negaitve e oneo

#

is coffect

#

or NO

steel venture
#

looks fine

sturdy haven
#

if i fail i will blzme you but i thinkz you did it right sonidk

#

BRUH

#

HOW THE FUCK

steel venture
#

😗

sturdy haven
#

!rotates

#

!rotate

steel venture
#

,rotate 270

sturdy haven
#

!rotation

obsidian monolithBOT
steel venture
#

dawg i taught you how to do it

sturdy haven
#

nomber feiv

#

but this oens hard

#

its amplificationals and uhh FREQUENCY

steel venture
#

you just need to plot points until ou find the shape

sturdy haven
#

listen my frenh

#

how is y POINTS

steel venture
#

listen my guy i got some sleep to catch up on

sturdy haven
#

LIKE ONE AND NEGATIVE ONE

steel venture
#

think about it

#

plot points and figure out what the maximum and minimum y values can be

sturdy haven
#

i like you

steel venture
#

😄

molten forge
#

How do you do this? It's in an online worksheet

#

They didn't explain how

viscid thistle
#

@sturdy haven still need help?

sturdy haven
#

YES

#

hwo do i do this

#

@viscid thistle

viscid thistle
#

Ok lets move to delta questions

maiden furnace
#

how would i go about to solve this

stuck lark
#

think in reverse, think of an angle x between 0 & pi such that cos(x)=-1/2

tardy ridge
#

two values I think?

unique hill
#

one angle

#

between 0 and pi

tardy ridge
#

where are the restrictions

#

there should be 2

unique hill
#

there's 2 if restriction is 0<x<2pi

#

so depends

tardy ridge
#

yeah

dim basin
tardy ridge
#

1 thing is that theta is in the 4th quadarant

dim basin
#

yep

tardy ridge
#

are you supposed to use a formula or something for this?

#

what's stopping you from just saying theta=-80.53

dim basin
#

tbh we did this before corona/spring break and its been 3 weeks since we have done this so i completly forgot how lol

#

oh

tardy ridge
#

and just plugging the value in

dim basin
#

waity

#

idk im in the wrong chat btw

#

i should be in early university

#

sry

unique hill
#

i think you're fine

dim basin
#

ok

glad vale
#

The perimeter of a stadium is an ellipse with major axis 640 feet and minor axis 549 feet. Find the distance between the foci of this ellipse.

#

giw di u di this?

#

how do i do this lol sorry

maiden furnace
#

ok i need someone to walk me through this one i managed to solve my other problem

#

so i know the answers isnt 7pi/6 because of the restriction of inverse cos being between 0 <= x <= pi

#

so what do i do next?

tardy ridge
#

well cos (pi+theta)=-cos(theta)

#

so cos 7pi/6 is -cos pi/6

#

and you can calculate that

#

also the answer would be 7pi/6 and another value if there wasn't that restriction, don't think 7pi/6 isn't right though

maiden furnace
#

well back of the book we have answer and it says the answer is 5pi/6

#

and going through some website it says to use the refence angle

tardy ridge
#

it is 5pi /6

#

but 7pi/6 is also an answer if the restriction wasn't there

#

do you know cos (pi+theta)=-cos(theta)

maiden furnace
#

no i dont know thecos (pi+theta)=-cos(theta)

tardy ridge
#

you could use that and change cos(7pi/6) into -cos(pi/6)

#

oh it's because of the unit circle

#

do you know the unit circle

maiden furnace
#

yup

tardy ridge
#

do you see how for quadarants 2 and 3 cosine is negative

#

because it's adj / hypo

maiden furnace
#

wait

#

is that just a refence angle?

tardy ridge
#

and adj is negative

#

what?

maiden furnace
#

is that just a reference angle?

tardy ridge
#

theta?

maiden furnace
#

well u get theta bar i believe

#

unless im just confusing my slef

tardy ridge
#

theta is a variable angle

#

if that's what you mean

#

theta is usally a variable referring to angles

#

and cos pi/6 is cos 30 which is sqrt3/2

#

that's also on the unit circle

#

since we are taking the arcos of -sqrt3/2 it's in the 2 or 3rd quadarant

#

but by the restriction it can only be the second one

#

which would be 180-30 degrees

#

150 degrees

#

did you know that cos (180-theta) also equals -cos theta?

maiden furnace
#

nope i didnt know that

tardy ridge
#

well it'll be hard to explain

maiden furnace
#

well looks liek this math teacher missed out on alot of information in that case

unique hill
#

have u learnt ASTC?

maiden furnace
#

yeah

unique hill
#

pretty sure ASTC covers that

slate oracle
#

Can anyone help with this..?\

tardy ridge
#

draw a triangle

gaunt bay
#

if someone can pm me. i know that i should use tan but i keep getting a negative number and not a big enough number

unique hill
#

looks like the channel's taken

#

@slate oracle draw a diagram of the building and the shadow

slate oracle
#

@unique hill

#

Sorry if it's messy

unique hill
#

nice aight

#

now what is the question asking?

slate oracle
#

For the measure(in feet) of the shadow and top of building.

unique hill
#

angle between the end of shadow and vertical side of building from the person

slate oracle
#

Yes.

unique hill
#

but yes

#

now what would be the appropriate trig ratio to use here?

slate oracle
#

Tangent..?

unique hill
#

that's correct

slate oracle
#

So then, tantheta= 100/230.. correct?

unique hill
#

yes

slate oracle
#

And then we would move tan to the other side making the equation theta=tan^(-1)100/230

#

Right?

unique hill
#

yep

slate oracle
#

So then, we would find the degree.. which is.. ~23.

#

Right..?

#

Would be estimate the degree or not?

unique hill
#

if it's rounded to one decimal place, it's 23.5 degrees

slate oracle
#

Yeah yeah, 23.498...

#

So then, what would be do afterwards?

unique hill
#

it says to the nearest degree

slate oracle
#

Oh, sorry.

unique hill
#

round to nearest degree

slate oracle
#

So it's 25 degrees..?

unique hill
#

so that would be 23 degrees

#

nono the 49856.... after the decimal place rounds down

slate oracle
#

You said it's 23.5 which is 24.

unique hill
#

no that's if its rounded to one decimal place

slate oracle
#

Okok

#

So what would we do now that we know the degree is 23?

unique hill
#

that's it, you've found the angle

slate oracle
#

I'm stuck here..

#

WHat?

unique hill
#

yeah that's the answer

slate oracle
#

oH.

#

Thanks for helping, Night

unique hill
#

np

slate oracle
#

Help..?

#

I drew this up.

unique hill
#

just make sure the 47 degree angle is clear

slate oracle
#

Oh ok

#

Can you verify my steps?

unique hill
#

your diagram looks correct

slate oracle
#

I would use sin, which leads it to being sin35=x/59 which would make x=(sin35)(59). Then x would be 33.84 or ~34 meters.

#

Ye?

unique hill
#

uh not sine

slate oracle
#

Then what..?

unique hill
#

are u aware of the trig ratios?

#

for sine, cos and tan?

slate oracle
#

sohcahtoa?

unique hill
#

yes

#

sine is opp/hyp

#

but 59 is none of those

slate oracle
#

cosine?

unique hill
#

ok first, dont guess

slate oracle
#

ok

unique hill
#

what's the trig ratio for cosine?

slate oracle
#

adj/hyp

#

And since we're finding for oppo, that's why I chose cos..

unique hill
#

where's the 'opp' in cos?

#

you said that it's adj/hyp

slate oracle
#

Uh. I don't know.

unique hill
#

ok you're trying to find the height of the building right? excluding the radio tower

slate oracle
#

Yeah, which would be considered the opposite.

unique hill
#

mhm, and you are given the distance of the person to the building, which is adjacent

slate oracle
#

Yeah

unique hill
#

you need to find the opposite and you are given the angle and adjacent

#

so what trig ratios would u use?

slate oracle
#

We would use tangent because that's the ratio with oppo and adj?

#

oppo/adj*

unique hill
#

yes correct

#

so what does tan 35 equal?

slate oracle
#

It's 0.46..

#

7*

unique hill
#

uh okay, first tan 35 = opp/adjacent correct?

slate oracle
#

so (tan35)(59) is 41.31 or ~41

#

wait

#

MB

unique hill
#

you follow?

slate oracle
#

Yeah

#

Wait.

unique hill
#

the tan ratio is opp/adj, and you are given the adj

slate oracle
#

Yeah but not the oppo.

unique hill
#

$tan{35}=\frac{height of building}{59}$

obsidian monolithBOT
slate oracle
#

Yeah

unique hill
#

ignore the spacing

#

do u get that?

slate oracle
#

Yes.

#

Then we would seperate the heightofbuilding

unique hill
#

yes, you make the height the subject

slate oracle
#

So multiply everything by 59

viscid thistle
#

hey does anybody know a simple way to solve this problem?

unique hill
#

@viscid thistle this channel's taken

slate oracle
#

Making the equation (tan35)(59)

viscid thistle
#

?

gaunt bay
#

@viscid thistle im waiting for someone to help me next

slate oracle
#

(tan35)(59)=~41

unique hill
#

@slate oracle yes, that's correct

#

yep looks good

slate oracle
#

So then what would be doo

unique hill
#

you have just found the height of the building, excluding the height of radio tower

slate oracle
#

Subtraction?

#

So do we find the second part now?

unique hill
#

the second part is find the height of building and the radio tower together

slate oracle
#

Ok