Question

What is the inverse of f if….

Answer 1

\[f(3) \sqrt[3]{x-2}\]

Answer 2

\[f(x)=\sqrt[3]{x-2}\]
?

Answer 3

\[f(3)=\sqrt[3]{x-2}\]

Answer 4

i forgot to put an = sign the first time

Answer 5

are we finding f'(3)

either way to get the inverse, let's replace f(x) with y
\[y = \sqrt[3]{x-2}\]
switch x and y
\[x = \sqrt[3]{y-2}\]
cube both sides
\[x^3 = {y-2}\]
\[x^3+2=y\]

Answer 6

\[x^{3}+2=y^{3}\] is that right?.. i have no idea I'm so stressed

Answer 7

How'd you get y^3?

Remember that square roots and squares are inverse operations, right?
\[(\sqrt{x})^2 = x\]
\[(\sqrt[3]{x})^3 = x\]

Answer 8

oh i got confused i thought you said for ME to cube both sides lol. I'm sorry I'm extremely tired and have to get a bunch of work done by like tomorrow. ughhh. my bad

Answer 9

lol no worries, just always go over your work a bazillion times so that you can prove to yourself that your answer is right.

ANYHOW, the inverse is now f(x) =x^2+2
f(3) = 3^2+2 = ??

Answer 10

wait so the answer is f(x) =x^2+2 ?

Answer 11

whoops./ you generally say inverse with a little dash f'(x)

so the equation for the inverse is f'(x) = x^2 + 2
then you plug in 3 into the inverse equation (assuming that's the question)

Answer 12

heres the actual question with the answer choices so you can see

Answer 13

god damn. I kept saying x^2 +2 but I meant x^3 + 2

Answer 14

hahah so is it the 3rd option then?

Answer 15

it is, it is...

Answer 16

thank youuu! i have another question! do you mind helping me??

Answer 17

are you gonna post it here or make a new question? I don't mind

Answer 18

ill post it here! and thanks! (:

Answer 19

uh you'd multiply by the conjugate. pardon my handwriting

Answer 20

i dont understand...

Answer 21

to simplify radicals you multiply by the conjugate pair which means flipping the sign

Answer 22

why do you have that answer selected?

Answer 23

what do you mean that answer selected?

Answer 24

what are the answer choices?

Answer 25

the ones with the bubble next to them on the link i posted!

Answer 26

rofl I didn't see it scrolled down a bit.

Answer 27

hahahah its all good! (:

Answer 28

so what is the answer?

Answer 29

Perform the operation bibby suggested and then simplify.

Answer 30

you can use wolfram if you don't like learning http://www.wolframalpha.com/input/?i=%28sqrt%283%29-sqrt%286%29%29%2F%28sqrt%283%29%2Bsqrt%286%29%29

Answer 31

its not that i don't like learning its that i am in a hurry and i have no idea whats going on.

Answer 32

\[\frac{\sqrt{3}-\sqrt{6}}{\sqrt{3}+\sqrt{6}} \cdot \frac{\sqrt{3}-\sqrt{6}}{\sqrt{3}-\sqrt{6}}\]

Do this multiplication here.

Answer 33

Why are you in a hurry? Is this a test?

Answer 34

idk how to..

Answer 35

i had to go out of town so I'm behind on a bunch of work due like really soon

Answer 36

So you don't know how to multiply something like this (a+b)(c+d)?

Answer 37

A lot of Americans like to use this thing called the foil method.

Answer 38

i have heard of it but idk how to really use it

Answer 39

(a+b)(c+d)=ac+ad+bc+bd

Answer 40

all you did was distribute those right?