#precalculus

1 messages · Page 16 of 1

potent remnant
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help please

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<@&286206848099549185>

woeful galleon
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What does concave Down mean

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I think a) -8<x<5 as the slope= rate of change

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Not sure about b but I think c) -infinity < x < -8 as it increases to 0 at -8 it means that the slope itself was negative initially so it fits

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Just joined the server so hope that helps

red crane
woeful galleon
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Ok

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Sorry I don’t do the American curriculum so I don’t understand much terms

red crane
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The tangent line has to be above the graph in the vicinity of the point

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Just like imagine x^2

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But inverse

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It’s curving down

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Y=-x^2

woeful galleon
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Ah gotcha

red crane
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Is concaving down

woeful galleon
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Ok then it’s increasing -> 0 -> decreasing

hallow pilot
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Has anyone taken AP calc BC?

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And if so, how fast did it go?

red crane
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Very fast

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You do calc 1 and 2

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Albeit generally most schools have you take it all 180 days

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But it’s a lot every day

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What grade are you in?

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@hallow pilot

proud crescent
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<@&268886789983436800>

visual minnow
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hi, any tips for studying precal?

north cloud
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Use khan academy

viscid thistle
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can anyone teach me the basics? i have tons of question when i study so ill need someone who has a patience and can answer my questions😅

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calc 1

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im struggling please help the poor man

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help me solve this

summer ruin
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have you computed g(f(x))?

viscid thistle
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my past teacher didnt have enough time to teach us that

summer ruin
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replace every appearence of x in g(x) with f(x)

viscid thistle
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f[g(x)]

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?

merry goblet
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g(f(x))

summer ruin
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that's the opposite of what I saidhmmCat

merry goblet
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so take f(x) and plug it into g(x)

viscid thistle
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oh okay

viscid thistle
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no bracket?

merry goblet
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no brackets

viscid thistle
merry goblet
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right

viscid thistle
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what is next

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wait

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can u guys wait for like 10mins

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my moms complaining that im using my phone while eating

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so that later ill just write it on my paper

merry goblet
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next just simplify it. turn it into one fraction.

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that should give you values for alpha, beta, and gamma

viscid thistle
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is the y called gamma

merry goblet
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yes

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they're some of the most commonly used greek letters

viscid thistle
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@merry goblet

viscid thistle
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like a(1/x-2)^a?

junior plover
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you dont need to sub f(x) in there

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your final answer will look like that after solving.

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g(f(x)) is f(x) subbed in place of x in g(x).

merry goblet
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square what's inside the parentheses

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then add the 2 to that fraction

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dont plug in any greek letters

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just simplify the expression
[1/(x-2)^2]+2 so that it's only one fraction

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from there you can figure out what each greek letter is equal to just by looking at it

merry goblet
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what

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what is 2

viscid thistle
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wait

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why did i type that

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nvm that

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what should i do next

merry goblet
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well where are you

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what have you got

viscid thistle
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the (x-2)^2

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or it stays like that

merry goblet
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yeah expand it

viscid thistle
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is the answer (x-2) (x+2)?

viscid thistle
merry goblet
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what no

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you're squaring it

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so (x-2)(x-2)

summer ruin
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it is not and doing anything with the denominator doesn't bring you any closer to actually answering the question

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why not just combine 2 and 1/(x-2)^2

merry goblet
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you're gonna have to expand it regardless

summer ruin
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no, denominator contains no gamma

merry goblet
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i mean yeah i guess, but it's probably good to expand it and make sure the greek letters line up

viscid thistle
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from the denominator?

viscid thistle
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and help me solve it

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i kinda understand it more when i look at another same problem

merry goblet
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what exactly are you having difficulty understanding?

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then maybe we can tailor a problem around that

viscid thistle
merry goblet
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you need to just simplify the expression so that it's one fraction

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only then can you see what a, b, and y are

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you won't be able to see it otherwise

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it will line up, like if i have 2x+3 and ax+b, then i know that a is 2 and b is 3

viscid thistle
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oohhhhh

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okay

merry goblet
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yeah, you just need to finish up the expression. that's it

viscid thistle
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waittt

merry goblet
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so add 2 to 1/(x-2)^2

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$\frac{1}{(x-2)^2}+\frac{2}{1}$

obsidian monolithBOT
viscid thistle
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waitt

merry goblet
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yes. just make it one single fraction

viscid thistle
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let ne resend the problem so that i dojt have to scroll up again

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will the answer be 2x^2 - 8x +9 / (x-2)^2

viscid thistle
merry goblet
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yes?

viscid thistle
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can u teach me how to add it

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i probably forgot it

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i want to recall

merry goblet
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so to add fractions you need common denominators right?

viscid thistle
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yes

merry goblet
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so multiply 2/1 by (x-2)^2/(x-2)^2

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then both fractions will have the same denominator

viscid thistle
viscid thistle
merry goblet
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yeah one sec

viscid thistle
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okie

merry goblet
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$\frac{2}{1}*\frac{(x-2)^2}{(x-2)^2}$

obsidian monolithBOT
viscid thistle
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so y said

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u said

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in order to add fractions i need common dnominators first

merry goblet
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right

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and here we're multiplying

viscid thistle
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wait a sec

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where did u get the

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fraction

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that

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(x-2)^2

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over (x-2)^2

merry goblet
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well we're adding 1/(x-2)^2 and 2 right

viscid thistle
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yes

merry goblet
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so i want my 2 to have the same denominator has 1/(x-2)^2

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so i'm going to multiply my 2 by (x-2)^2/(x-2)^2

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which is the same thing as multiplying by 1

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any expression or number divided by itself is equal to 1

viscid thistle
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okayyy

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okay okay

merry goblet
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so right now we have $\frac{1}{(x-2)^2}+\frac{2}{1}*\frac{(x-2)^2}{(x-2)^2}$

obsidian monolithBOT
viscid thistle
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okayy

merry goblet
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which is the same as $\frac{1}{(x-2)^2}+\frac{2}{1}$

obsidian monolithBOT
merry goblet
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i just multiplied 2/1 by 1

viscid thistle
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okay

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since the last part is equal to 1

merry goblet
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since the last part is equal to 1 it doesnt change the expression

viscid thistle
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yes

merry goblet
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but it makes it so that i can now add the 2 to the fraction 1/(x-2)^2

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so it becomes$\frac{1}{(x-2)^2}+\frac{2*(x-2)^2}{(x-2)^2}$

obsidian monolithBOT
viscid thistle
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yehhh

merry goblet
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and since both fractions have the same denominator i can now add them together

viscid thistle
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yeahhhh

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so what is next

merry goblet
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so now we add the numerators together to make 1 fraction

viscid thistle
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okay

merry goblet
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$\frac{1+2*(x-2)^2}{(x-2)^2}$

obsidian monolithBOT
merry goblet
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does that make sense how i did that

viscid thistle
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3•(x-2)^2/(x-2)^2

viscid thistle
merry goblet
viscid thistle
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wait

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so whats going to happen

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i thought we are adding

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both constant no.

merry goblet
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yes but for example 1+5y does not equal 6y

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just expand the (x-2)^2 and then multiply it by 2

viscid thistle
merry goblet
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yes

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what does that equal

viscid thistle
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2x - 4 + 2x - 4?

merry goblet
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you remember pemdas yeah? you gotta do the exponent first, then multiply

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so do (x-2)^2, then multiply by 2

viscid thistle
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in pemdas
parenthesis first

merry goblet
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there is nothing in the parentheses you can do to simplify it, so we move to exponent

viscid thistle
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can u show me the answer

merry goblet
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so (x-2)^2=(x-2)(x-2)

viscid thistle
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yes

merry goblet
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which is x^2-2x-2x+4

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so $(x-2)^2=x^2-4x+4$

obsidian monolithBOT
merry goblet
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and now we have to multiply by 2, because we have 2*(x-2)^2

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$2(x-2)^2=2*(x^2-4x+4)$

obsidian monolithBOT
merry goblet
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so $2*(x-2)^2=2x^2-8x+8$

obsidian monolithBOT
merry goblet
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does that make sense?

viscid thistle
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waittt

viscid thistle
merry goblet
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(x-2)*(x-2)

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you FOIL it out right?

viscid thistle
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yeah

merry goblet
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and we got x^2 - 2x - 2x +4

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i added the 2x's together to get 4x

viscid thistle
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OHHHH

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okayyyy

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i get it now

merry goblet
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so it simplifies to x^2-4x+4

viscid thistle
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okayy

merry goblet
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okay so now

viscid thistle
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wait

merry goblet
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yea?

viscid thistle
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oh okayy

viscid thistle
merry goblet
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mhm

viscid thistle
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the next thing we have to do is to multiply 2 to (x-2)^2 which will give us 2x - 4

merry goblet
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no we just did 2*(x-2)^2

merry goblet
viscid thistle
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oh thats the final answer?

merry goblet
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no

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remember the big fraction we had

viscid thistle
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OHHHH

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OKAY

merry goblet
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okay so here's where we're at

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$\frac{1+2x^2-8x+8}{(x-2)^2}$

obsidian monolithBOT
viscid thistle
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yow dude im sorry i thouht it was different from the other

merry goblet
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no you're good. it's tough stuff. i get it

viscid thistle
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thank you so much man for helping me

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okay move on

merry goblet
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okay so you see how we got to this point yea?

viscid thistle
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yesss

merry goblet
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perfect. okay so now we add the 1 and 8

viscid thistle
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so 9?

merry goblet
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$\frac{2x^2-8x+9}{(x-2)^2}$

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right

obsidian monolithBOT
viscid thistle
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2x^2 - 8x + 9

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OH YEAHHH

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okay

merry goblet
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yes perfect

viscid thistle
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so back to the provlem

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says that i have to find these letters

merry goblet
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so we're really close to finding alpha, beta, and gamma

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if we expand the denomintor we will see it clearly

viscid thistle
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greek

merry goblet
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those are greek letters

viscid thistle
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oh yeah greek

merry goblet
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yea

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okay so expand the bottom

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foil it out

viscid thistle
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so the a is 2 then the 8 is b and y is 9

merry goblet
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almost

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a and y are correct

viscid thistle
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mhm

merry goblet
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so you have a -8x and a +2Bx

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so then -8=2B

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you see where i got that?

viscid thistle
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what made the 8 turn negative

merry goblet
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it's being subtracted. it's the same thing as saying 2x^2+(-8)x+9

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did that make sense

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$2x^2-8x+9=2x^2+(-8)x+9$

obsidian monolithBOT
viscid thistle
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what number before it turns -8

merry goblet
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could you rephrase that

viscid thistle
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i mean like

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did 8 change another number

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like

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aaa let me translate it

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YEAH

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what replaced -8

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WAIT

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no nvm it sorry

viscid thistle
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what the heck is wrong with me

merry goblet
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lol

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i was like uh how do i explain this

viscid thistle
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im sorry dude LOL

merry goblet
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no you're good lol

viscid thistle
merry goblet
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do you see why -8=2B though?

viscid thistle
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yes

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its the same place

merry goblet
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right. okay so what is beta then

viscid thistle
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16?

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wait

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its 8

merry goblet
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no.

viscid thistle
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the beta is -8

merry goblet
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$-8=2{\beta}$

obsidian monolithBOT
merry goblet
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divide both sides by 2

viscid thistle
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-4

merry goblet
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right

viscid thistle
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OHHHH

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WAIT

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so

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if it only find the b

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we get -4

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but if its 2b

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we have to multiply it by 2

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??

merry goblet
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and it would give us back the -8 that we started with yes

viscid thistle
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OKAYYY

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but wait

merry goblet
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but b=-4

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which is all we needed

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since we already have a and y

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so a=2, b=-4, and y=9

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now solve a+2b+y

viscid thistle
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2-8b+9

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is that correct

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since its 2b

merry goblet
viscid thistle
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yeah

merry goblet
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so a+2b+y=(2)+(-8)+(9)

viscid thistle
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oh okay

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i have to put it in a parentheses

merry goblet
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no i just did that to make it clear

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so what is a+2b+y equal to

viscid thistle
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2+(-8)+9

merry goblet
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which is

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what

viscid thistle
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i still have to do the pemdas righ

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t

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or no

merry goblet
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if you add a negative, it's the same as subtracting the positive

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so $2+(-8)+9=2-8+9$

viscid thistle
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11 - 8 is 3

obsidian monolithBOT
viscid thistle
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so the answer is 3

merry goblet
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yep!

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ironically i added this incorrectly originally and got 1 lol

viscid thistle
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LOL

merry goblet
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yeah idk man

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good job tho!

viscid thistle
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MAN

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WAIT

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i feel like i wanna solve it now

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even tho it only wants to find the greek letters

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wait

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is it even solvable

merry goblet
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it's not something you solve. it's just a function

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you could graph it if you wanted, but that's about it

viscid thistle
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oh okayy

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okayyy

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MAN

merry goblet
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the final form is $\frac{2x^2-8x+9}{x^2-4x+8}$

viscid thistle
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why is hard math for me then for someone like u guys find it easy

obsidian monolithBOT
viscid thistle
#

yesh

merry goblet
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i've been doing math for like 20+ years at this point so

viscid thistle
#

woah

merry goblet
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that helps

viscid thistle
#

you must be a prof

merry goblet
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no just a degree

viscid thistle
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why dont u get masteral

merry goblet
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oh i plan to

viscid thistle
#

mhmmm

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i hope u get higher

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what is next to masteral again

merry goblet
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and i hope you do well in school!

viscid thistle
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i forgot

merry goblet
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after master's is phd

viscid thistle
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YEAH

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i hope you get that also

merry goblet
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haha. ty

thorn creek
#

the masters is optional in some programs

viscid thistle
# merry goblet and i hope you do well in school!

you know man actually im in college and im studying electrical engineering, when we were in senior high school.. our school system is bad so our subject in pre-calculus that we only took for 1 semester is not enough for us

thorn creek
#

at my alma mater the masters degree is what you get as a consolation prize for failing quals

viscid thistle
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im freshman btw

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do you guys have senior high

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like grade 11 and 12

merry goblet
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yeah.

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highest math class in my high school was calc

viscid thistle
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whattt

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we dont even have calc in highschool

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we only had mathematics thats all

merry goblet
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but i've heard other schools teach calc in like sophomore/junior year

viscid thistle
#

and when i turn gr11 we had general mathematics then gr12 pre cal

merry goblet
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yeah just depends on the area

viscid thistle
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its really bad for me to study this course not knowing the basics of calculus

merry goblet
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yeah that's tough. i wish you luck.

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it's like 4:30 here though so i'm headed off

viscid thistle
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you know man my classmates here in college are from stem strand that focuses on science,tech,engineering, math

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thats why they adv than me

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aaa

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i picked other strand

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i picked gas that focuses on generals

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thats why

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i kinda luck ỉn knowledge compare to them

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yeah enough with the story

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i just wanna learn math cause the relief when you finish it solving is a very good feeling

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anywayss

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THANK YOU SO MUCH MAN @merry goblet thank you for helping me and the other guy earlier that also helped me

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Anyone know what main parts of geometry are used in Pre-calc like major points and like HAVE to knows? cause my geometry level is kinda weak so i wanna know what to focus on so I don't get stuck behind

viscid thistle
leaden flint
#

can someone please help me with this question 🙏

summer crag
summer crag
#

Also notice that the avg. temp is max at d=7

leaden flint
#

ah i solved it, thank you

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🙏

void matrix
violet belfry
#

does anybody know about "The idiots guide to calculus. "

tired holly
#

i got fed up with the byu double angle stuff in unit 3 so i wrote some super simple python code to solve all double angle identities based on original angle measure which you can get from arc sin/tan/cos: here it is if anyone would like it:
import math
angle = float(input('input theta'))/180*math.pi

cos2_val = str(math.cos(angle2))
sin2_val = str(math.sin(angle
2))
tan2_val = str(math.tan(angle*2))

print('cos2theta = ' + cos2_val, 'sin2theta = ' + sin2_val, 'tan2theta = ' + tan2_val)

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sorry it should say angle*2 for cos2val sin2val tan2val if u want it to work

violet belfry
#

ok

scenic coral
#

Btw \* to cancel discord * for *italics*

#

also consider using
```python
code
```
which gives

print("hello world")
frigid trout
#

Does anyone have any YouTube video recommendations to learn pre calc from the beginning

thorn creek
#

the beginning of what, time?

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i generally recommend khan for precalc

frigid trout
#

Just like from start without any previous knowledge I meant

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Thank you will check it out!

storm lodge
scenic coral
#
#include <stdio>

int main() {
  std::cout << "fr\n";
}```
storm lodge
scenic coral
#

xd

viscid thistle
#

Hi, can someone explain the given solution to me?

spare wharf
#

How come 0.1 became 10? Thanks.

summer crag
polar meadow
spare wharf
#

Aghh

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Thank you!

quasi brook
#

could someone pls explain why the fundamental theorem of calculus is true?

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like WHY can the antiderivative of a function be used to calculate the area under the curve

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i'm not understanding the wiki page

summer ruin
#

if you want a proof - you can just search for it

velvet sequoia
# quasi brook like WHY can the antiderivative of a function be used to calculate the area unde...

Let F(x) be the area under f from 0 to x. Then increasing the value of x means shifting the right-side boundary of the area more towards the right. If f is high up at the right boundary, then shifting the boundary leads to a quick increase in area. If f is close to the x-axis at the right boundary, then shifting the boundary leads to almost no change in area. So as you shift the right boundary, you would expect the rate of increase of the area F(x) to be proportional to the value of f at the right boundary (that is, f(x)).

#

And it turns out that you have F'(x) = f(x) for "nice enough" functions

quasi brook
#

but I didn't understand some parts of it

quasi brook
velvet sequoia
#

Ye

quasi brook
#

but i didn't get the proof

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like

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here's an img

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I got this so far

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but I didn't understand this

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like i didn't understand after h1 and h2 are introduced

velvet sequoia
quasi brook
#

💀

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so someone who's still in hs, the actual proof is too advanced?

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rip

velvet sequoia
#

If by an "actual proof" you mean properly defining stuff like limits, continuity, integration instead of using pictures and vague wording

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Then it's analysis

quasi brook
#

oh rip

#

ty for the explanation!

velvet sequoia
#

But there's nothing stopping you from studying it if you're interested

quasi brook
#

hm

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what kind of prior knowledge would be required?

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like for calculus you need to have a good grasp of trig/algebra

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anything like that needed for real analysis?

velvet sequoia
#

Sets and experience in working with rather abstract stuff

#

The most basic parts of analysis are just making calculus rigorous so knowing calculus beforehand would let you know what it's trying to do

summer ruin
#

you basically can't properly do any math without acing everything in high school math, basic calculus knowledge includes sequences, limits and continuity

quasi brook
#

prob won't be studiyng it any time soon though 💀

viscid thistle
mellow vigil
#

its one of the best playlist for UNDERSTANDING Calculus

viscid thistle
#

GUY
i have an exam on monday
MATHS - indefinite integration and conics
PHYSICS - magnetic effects of current, magnetism and mattter, current electricity, heating effects and instruments
CHEM - amines, carbonyl compounds, carboxylic acids and chemical kinetics
(tips pls_
i did complete most of it but im scared of chem and conics

#

guys i mean

hallow pilot
#

I have done studying of calculus over the summer

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I have gotten currently up to curve sketching, but I am going to start integrals before I start school on Tuesday

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I have not come across anything that is very difficult so far

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And I have been able to work through a lot of it on my own

viscid thistle
#

Can someone help me here?

queen cargo
#

heyy can someone help me on a question

frigid crag
#

im scared but lets see ^^

warped cipher
viscid thistle
warped cipher
#

i think you got a wrong channel

viscid thistle
#

Oh

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Well can you help me anywho

#

In dms?

warped cipher
#

no, this is exam

#

I can't help sorry

queen cargo
#

can someone still help me

radiant kite
#

with what

queen cargo
#

lIf the domain of f is all real numbers in the interval​ [0,8] and the domain of g is all real numbers in the interval ​[-​3,4], the domain of f+g is all real numbers in the interval​ _______.

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i know the answer is [0,4] but how do I get that answer

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no worries i got it

ebon moat
#

yo guys how do I solve num 3? I'm done with 1 and 2 but I don't know what to do on num 3

willow bear
#

to cut away the black bands about 1.5 times as tall as the image itself...

#

@ebon moat you're given the equations of some circles, you're asked to read off their centers and radii

ebon moat
#

how do I do that

willow bear
#

do you know in general what the equation of a circle looks like?

ebon moat
#

is it the
x²+y²=r²? or is it some other variation of it?

willow bear
#

$(x - h)^2 + (y-k)^2 = r^2$, where $(h,k)$ is the center and $r$ is the radius.

obsidian monolithBOT
willow bear
#

you need to massage your equations to look like this form, though

ebon moat
#

how do I do that

junior plover
#

<@&268886789983436800> urgent!

hollow hedge
#

got it

junior plover
#

these shits are increasing

hollow hedge
#

they're just hacked accounts

junior plover
#

oh

solar olive
viscid thistle
#

can anyone help me

solar olive
#

f(g(x)) = 2(x+2)^2-(x+2) -2

#

g(f(x)) = (2x^2-x-2) +2

thorn creek
#

i do not like questions like that

feral halo
#

would it be 6xh + 3h^2 + 4?

#

I'm really confused can someone help me on this

late geyser
#

an h should cancel out of every term, not just the last one.

versed vapor
#

I am confused 🆘

queen cargo
#

can someone help me

#

quickly

#

this things due in like 10 minutes

#

I have no idea

#

how to do this

queen cargo
#

no worries

viscid thistle
#

hello chat

radiant kite
#

help

radiant kite
#

please guys help 😩

untold spindle
#

<@&268886789983436800>

obsidian monolithBOT
#

Dyssrupt

timber spindle
#

Will I be ok in Calc 1-2 if I’m not good with conic sections?

severe moat
#

how long, realistically ofc, would it take to learn college level calculus if the most advanced math class ive taken is algebra 2 with statistics?( looked into trigonometry by last unit)

short saffron
#

Can I ask a basic topology question here?

deft cypress
tawdry viper
#

@everyone

#

I need a tutor

#

for precalc

#

I can play

#

pay

untold spindle
#

use khan academy, its free

tawdry viper
#

oh okay, but its not that good at explaining

untold spindle
#

also dont ping everyone, it doesnt even work

tawdry viper
#

oh nvm

#

sorrry

#

for the troubles

untold spindle
#

if you need elaboration upon a topic you can always ask in this server

tawdry viper
#

ok

#

what math are you in?

untold spindle
#

college algebra, but it hasnt started yet

tawdry viper
#

what grade?

untold spindle
#

11th

tawdry viper
#

ah I see

#

im a freshman lol

#

I need help

untold spindle
tawdry viper
#

2^x=(.0625)^-14

#

Solve for x

#

@untold spindle

fresh agate
#

once i know more math ill probably understand what this sever is talking about

rough birch
tawdry viper
#

huh

rough birch
#

lme double check

untold spindle
tender questBOT
# rough birch 2.46

As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.

rough birch
#

@tawdry viper

tawdry viper
#

yah

#

I think thats right

rough birch
#

it is

untold spindle
#

i just told you not to give out solutions

rough birch
#

one time dude chill out

#

I'll explain

#

First, simplify (.0625)^-14

#

it becomes

#

2^x = 16^14

#

To solve for x, take the logarithm base 2 of both sides

#

x * log2(2) = 14 * log2(16)

untold spindle
#

still, its better to have them work through the problem themselves with you guiding them along the way, instead of having an explanation handed to them on a silver platter.

viscid thistle
#

how does it simplify to 16^14?

rough birch
#

simplification

#

?

warm frost
#

does anyone have the pdf version of this book? thanks

viscid thistle
thorn creek
#

there ar efour listed authors but they're illegible in that image

#

first one looks like demora maybe

#

so itr's demana, not demora

viscid thistle
#

Found the 8th edition lol

thorn creek
#

the 7th edition is from 2006, not that precalc has materially changed in the past 50 or 60 years

viscid thistle
#

Yeah I think someone did a sweep on it and took down all the sites with it for free .-. pair that with premium pdf .com or something that spammed sites tryna grab your credit card

#

You can find other editions (namely 8 and I think 10) and there are quite a few sites that tell you the exact answer to every problem in the book, but yeah I don't think you can find edition 7

warm frost
#

Hmm okay

#

Thank you

#

I found edition 8

shy sonnet
#

Does anyone know how to solve this?

zenith stirrup
pine light
#

Can someone help me? I don't understand the last part, how does plugging in the x-coordinate of min prove B^2<AC? Like, shouldn't it be independent from x?

#

Proof of Cauchy-Schwarz btw

ornate lion
#

whats pie

zenith stirrup
short saffron
#

Can a continuous function that is strictly increasing and strictly decreasing on an interval have an inverse? If not, why?

willow bear
#

but also how are you gonna have a function be both strictly inc and strictly dec at the same time...

pine light
radiant kite
#

ping me

pine light
prime peak
#

can someone help pls 😭

#

i forgot how to do these

untold spindle
#

You got the factored form already so that's good, now all you need to do is set each of the factors equal to 0

#

And solve for x

prime peak
#

yeah i did that

#

but for some reason its wrong

untold spindle
#

Well how did you get -1?

prime peak
#

oh shoot

#

wait that still wrong tho

untold spindle
#

Ohh I see, "enter all answers including repetitions"

prime peak
#

yeah i get it you write the double 0 twice

untold spindle
#

The double 0?

prime peak
#

yeah

#

answer is

#

1/2, -2, 4, 4

untold spindle
#

Ah yes good job👍

#

!nosols

tender questBOT
#

As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.

radiant kite
queen cargo
#

heyy can some help me

void thorn
# radiant kite

hint: you can rewrite this in terms of the definition of derivative of e^(-cos x) at x=0

queen cargo
#

please help me 😭😭

#

im dying here

queen cargo
#

no worries

tawny veldt
#

i can’t tell which i disliked more pre cal or trig

#

they’re very fun when not for school

quiet falcon
#

going into precalc this year, anything i should be prepared for?

warped cipher
scenic coral
#

It's just trig identities? Or is discord not showing the other pins?

warped cipher
#

Well I mean to say Trig identities important in precalc so you could prepare for that

#

You could also do graphs iirc

zenith stirrup
radiant kite
#

or taylor series

#

or l'hopitals rule

void thorn
#

your funeral

radiant kite
#

there has to be a way

void thorn
#

there is depending on what you're willing to allow

radiant kite
#

just nothing that involves derivative

void thorn
#

is this allowed $$\ln(x)=\lim_{h \to 0} \frac{x^h-1}{h}$$

obsidian monolithBOT
#

Merosity

radiant kite
#

how did u get that

#

but yea sure that is allowed

vapid plaza
#

[ \frac{e^{- \cos x} - e^{-1}}{x} = e^{-1} \frac{e^{1 - \cos x} -1 }{1 - \cos x} \frac{1 - \cos x}{x^2} x]

void thorn
#

basically the limit definition for e^x but turned inside-out

obsidian monolithBOT
#

elon mask

vapid plaza
#

Oh it looks ugly bruh

void thorn
#

you can then substitute h=1-cosx

vapid plaza
void thorn
#

since as x->0 in 1-cos x you have h->0 that turns it into lim_{h->0} (e^h-1) / h which...

radiant kite
#

how did u get 1-cosx in the denominator?

#

@vapid plaza

vapid plaza
#

Bro I wrote that whole thing

radiant kite
#

oh its multiplied nvm

vapid plaza
#

Limit of (1-cos x) /x^2 can be found by using elementary methods and the fact that limit of sin x / x is 1

vapid plaza
radiant kite
#

arccos(1-h)

vapid plaza
#

No, we are solving for the limit of just $\frac{e^{1 - \cos x} -1 }{1 - \cos x}$ right now

obsidian monolithBOT
#

elon mask

void thorn
#

the denominator is 1-cos x, so just replace that entire denominator with h

vapid plaza
radiant kite
#

oh ok

#

then just basic limits stuff from there

mental ridge
#

i need help studying for precalc test tmrw

#

dm me looking to go in a voice call so you can help in depth

radiant kite
#

what is the test about?

mental ridge
#

rates of change

radiant kite
#

average rates of change?

mental ridge
#

change in tangent

#

yes

radiant kite
#

alr

mental ridge
#

and a couple more topics

radiant kite
#

i guess i can try to help you a bit

#

in like 15 mins

mental ridge
#

bet

#

just message me

radiant kite
#

alr

mental ridge
#

yo

radiant kite
#

yea

#

@mental ridge

#

im here

#

sorry it took this long

short saffron
#

If $p(x)$ is a polynomial function, then what is $p'(1/x)$?

obsidian monolithBOT
#

sunside

radiant kite
#

if p(x) was ax^n+bx^n-1+cxn^-2... and so on

#

then derivative of p(1/x) would be

#

nax^n-2+nbx^n-3... and so on

short saffron
radiant kite
#

because when u do the power rule the exponent becomes n-1

#

and then u divide by x

#

so it becomes n-2

#

oh wait

#

nvm

short saffron
#

The derivative of p(x) would be nax^n-1+nbx^n-2... and so on. So plugging in 1/x, we get na(1/x)^n-1+nb(1/x)^n-2+... what am I missing?

radiant kite
#

it is ax^1-n+ax^2-n... and so on

#

right?

short saffron
#

maybe, I'm unsure 🙂

#

we need to work some examples probably

#

like p(x)=1+x^2

#

I think it's like this @radiant kite : if p(x) is a polynomial function, then we can apply the chain rule for (p(1/x))'=-1/x^2 p'(1/x). Of course, this leaves us with p'(1/x).

frigid trout
#

im just starting out pre calc ex. for z= 8i−172 the imaginary number will always be whats before i so 8 and real -172

#

so if its -9i +8 imaginary would be -9 and real 8?

summer ruin
#

yes

frigid trout
# summer ruin yes

thank you, will those type of questions be formatted like that always and will there be more complex versions?

frigid trout
summer ruin
#

you should be relying on understanding instead of question formatting

rotund remnant
#

Hey guys, I want to study pre calc and gen math 1 in advance. What should I study first?

uncut mulch
#

basic algebra

#

geo

viscid thistle
#

quick question

#

how do i get 24x there again

#

i forgot

#

from expanding (4-3x)^2

#

yeah

#

but how

#

is it foil method?

#

= (4-3x)(4-3x)

doing FOIL

16 - 12x -12x + 9x^2
collect like terms
16-24x+9x^2

#

YEAHHH

#

okay

#

thank u

#

im just used to x^2 always at first

#

anyone interested in number theories

viscid thistle
#

This is right, right?

#

differentiating gets me 2sqrt(x)

viscid thistle
#

Is this correct?

#

ah ive multiplied wrong as well anyway should be x^0 not x^1

fresh kindle
#

dude someone be my study buddy have help me with math i love it and i am terrible at it 🥲

radiant kite
#

no lhopitals

charred frigate
# radiant kite

please don't post questions in multiple channels, especially in a channel that the question is unrelated to

untold spindle
#

the sin function gives different output depending on if your calculator is in degrees or radians

uneven oxide
#

the one on the right is in rads?

untold spindle
#

no, the left one is in radians, the right one is in degrees

#

check your desmos settings

uneven oxide
#

ok thank you

untold spindle
#

np

analog flower
#

these don't feel like they should be equal, and yet they are

north cloud
#

Woooah

#

How

#

Impossible

#

My eyes and brain hurt

obsidian monolithBOT
#

Dyssrupt

viscid thistle
viscid thistle
weary karma
#

could someone help me with online pre-calc?

slim steppe
# radiant kite

You could rewrite that as ln(x^x), and numerically test it

smoky nexus
#

Also simplify e^-1 & e^-cosx

tropic obsidian
#

Why does this work?

obsidian monolithBOT
#

Şêro

#

Şêro

tropic obsidian
#

which would make sense, but I guess my question then is where the cube came from?

obsidian monolithBOT
#

Şêro

tropic obsidian
#

oooh okay, thank you!

floral horizon
#

I’m finally able to understand messages in this channel now W

desert socket
#

im confused. shouldnt the 2nd part of the numerator be sinb/cosb...?

uncut mulch
#

yes

raw sinew
#

omg hi

shadow jay
#

i dont get this

#

can somebody please explain it for me? thank u sm :D

thorny cypress
#

you have a second order equation

#

do you know the geenral form of a circle?

floral horizon
proven spear
#

we need to convert it to the form (x-x_0)^2+(y-y_0)^2=r^2

#

just some basic algebra

#

the center would have the coordinated (x_0, y_0)

#

and the radius is r

hallow lodge
#

anyone know why they wrote vertices as that

summer ruin
#

as what?

#

these are coordinates of the vertices

hallow lodge
summer ruin
#

(1, -3) is the center of the ellipse

hallow lodge
summer ruin
#

it didn't change, (1,-3) is still the center of the ellipse

#

now you're adding or subtracting some number to x instead of y because coverticies are located along other axis

hallow lodge
#

with b^2 in the middle

summer ruin
#

what order?

hallow lodge
#

vertex has a^2 on the last part

#

while co vertex has b^2 in the middle

summer ruin
#

they don't, these are roots of a^2 and b^2

#

and obviously your question reduces to whether (1,-1) is the same point as (-1,1)

#

it isn't

#

the order in which you write coordinates depends on what point you're trying to describe

hallow lodge
summer ruin
hallow lodge
# summer ruin see this picture

ive done horizontal and vertical equations. they seen to have the same formula being, square rooting a^2 for vertex and b^2 for covert

candid jetty
#

I know it’s kinda sudden but I need some help with some Precalc

#

We have a quiz tomorrow and I’m struggling to understand. Has to do with functions

#

I can be more in depth, just give me a minute

#

Here’s a good example for one of the things I’m struggling with

#

I can answer the simpler ones, but this one I can’t figure out

#

There’s some other things but that was the first question I saw when I opened my MacBook

#

Just ping if anyone responds so I know to check here

#

Yes, but please don’t ask me to define it

#

Basically it’s a relationship between x and y. Usually I see them put on a table, with x on the left and y on the right. These points are used on a graph

#

I tried my best, but defining things is not my specialty

#

It’s ok if I use the usua f(x) right?

verbal garnet
#

so long as there is only one function named f at the same time

obsidian monolithBOT
#

kebesque integral

candid jetty
#

And when you’re given an x value, you can plug it into those x spots

#

40?

#

I’m struggling to describe it, but I’ll make an attempt

#

I need to plug it into the equation 4xpixr squared

#

I can’t find the pic symbol in my phone

#

Pi

#

Ohhhhhhh I see what I was doing wrong

obsidian monolithBOT
#

kebesque integral

candid jetty
#

I know pemdas, but I kept plugging it into parenthesis for some reason

#

I did the math for the first problem in the picture

#

I got 113 after rounding

#

It doesn’t tell me where to round to

#

Just to simplify

#

Squaring a fraction

#

I take 1 over 3

#

And square it

#

What would I be looking for?

#

Ah ok

#

I got 4 times pi over 9 for the second one

#

Only got the second one right

#

5-2(s+3)

#

Would I do distribution here?

#

Or whatever it’s called

#

Where I multiply both by 2

#

I got it!

#

Just have one more thing on this HW then I’ll be good to study

candid jetty
#

I got them all except for the last one, which is definitely tricky

#

Wait I may have found my issue

obsidian monolithBOT
#

Şêro

#

Şêro

candid jetty
#

7 plus 4 plus 6

#

Because -1 squared is positive 1

#

And two negatives make a positive

#

And 6 is 6

#

PEMDAS and all that

#

You end up with 17

#

Yeah I had gotten that one right

#

The only one I hadn’t gotten was the third one

#

I did that

#

Lemme type it out

obsidian monolithBOT
#

Şêro

candid jetty
#

Ok this is where I got confused

obsidian monolithBOT
#

Şêro

candid jetty
#

Wait what?

#

How did you get to that step?

#

That process in the middle is what stumped me

obsidian monolithBOT
#

Şêro

#

Şêro

#

Şêro

candid jetty
#

Kinda? We’re in a part that I struggle with now

#

Well

#

I can see what you’re doing

#

But I can’t replicate it when given different numbers

#

I struggle to read deeper into math

obsidian monolithBOT
#

Şêro

candid jetty
#

$y^2+2xyx6+12

#

Huh

#

Weird

#

Just try and read that I guess

#

So

#

y^2+12y+36

obsidian monolithBOT
#

Şêro

candid jetty
#

Ah ok

#

Can I have another?

obsidian monolithBOT
#

Şêro

candid jetty
#

Alright

#

Would I distribute first?

#

Hm

#

4z+12^2

#

4z^2+2xz+9?

#

That’s wrong, I know it

#

4z^2+2xZ+2x3+3^2

#

4z^2+2z+15

#

Is that right?

whole island
#

@candid jetty remember first, inner, outer last.

candid jetty
#

Sucks it can’t be FOIL

whole island
#

yes, foil.

#

if you follow these steps, include order of operations, you will get the answer

candid jetty
#

Ah ok

candid jetty
#

So I can do that now

#

I can determine what a function is

#

I know how to find intercepts

#

Y intercept, make xs 0

#

X intercepts, make y zero

#

I can determine symmetry of a line

#

Actually

#

I may need to work on determining symmetry with an equation instead of a graph

#

There’s other things I think

#

We only did half the chapter

dry sparrow
untold spindle
#

,rccw

obsidian monolithBOT
untold spindle
dry sparrow
#

i think i got it actually

#

-9x+3 after i used PEMDAS

untold spindle
#

Ok 👍

#

Could I see your work?

#

It doesn't sound quite right

dry sparrow
untold spindle
#

Oh that's not how you multiply binomials, what you should be evaluating is
(5x-7)*(2x+3)

#

!nosols

tender questBOT
#

As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.

digital valve
#

sorry

#

new to the sertver

untold spindle
#

It would be better for her to work it out herself rather than given the answer on a silver platter.

untold spindle
dry sparrow
#

thanks

#

yes thank you

#

cashapp?

untold spindle
#

Umm <@&268886789983436800> isn't this against the rules?

dry sparrow
#

was the answer he provided right tho?

untold spindle
#

Work it out yourself and you'll see

digital valve
#

10x^2-9x-18

untold spindle
digital valve
#

this is correct

untold spindle
#

I just told you not to give out answers

digital valve
#

she asked

#

if the answer was right

#

is the asnwr correct @raven lark

untold spindle
#

<@&268886789983436800> srry for second ping btw

digital valve
#

ur spamming the moderators?

#

why

dry sparrow
#

10x^2+x-21

#

this is uit

#

after working it out i got this not that @digital valve

modern valve
untold spindle
warped cipher
untold spindle
warped cipher
#

sadge

#

but im surprised tho

remote dune
viscid thistle
#

oh dam my dad made me do more math 😐 😐

short knot
#

How do I simplify this

#

I’ve been trying too but I’m confused bc you can only at like terms

odd yew
#

so you have -9*6i

#

which equals to -54i

#

which can be expressed in the standard form of a + bi

#

a = 0

#

b = -54

short knot
#

thank you

cloud flower
#

I just started learning about functions in precalc and i forgot everything from algebra

#

And i have no idea what im doing

#

How would you solve y=x^2 +-3

#

For example

scenic coral
cloud flower
#

Either or

scenic coral
#

Ok

scenic coral
cloud flower
#

Oh

scenic coral
#

A function must satisfy the vertical line test

#

Meaning a unique y must exist for every x in the domain

cloud flower
#

Okay well how would i solve a function without a number on x

#

Thats what i dont really get

#

Like for example

scenic coral
#

plus or minus would make it not a function due to it yielding 2 y values

cloud flower
#

F(x)=x+4

scenic coral
#

wdym by solve?

cloud flower
#

Like what would be my value

#

Or my output

scenic coral
#

x + 4 ...

cloud flower
#

Is that literally it

#

Is the output just x+4

#

Okay if thats the case would x=2y^2 be 4y

chrome galleon
#

How would i get x? I dont understand what I am looking at exactly.

cloud flower
#

Or 4x2 making thr output 8