Question

find (g·f)(3)


f(x)= 3x-2
g(x) = x^2

Answer 1

9

Answer 2

multiply what the functions are equal to together.

Answer 3

(g·f)(x) = g(x)·f(x)

So you multiply the two functions together:

g(x)·f(x) = (3x-2)(x^2)

to find (g·f)(3), just plug in x=3 into that^

Answer 4

I got 3x^3 - 2x^2

X = 9

Answer 5

is that right?

Answer 6

yes

Answer 7

that's funny bc its not one of the answer on my quiz D: ?????????

Answer 8

what are the answers that you have?

Answer 9

http://prntscr.com/2xmra4
^^^^ screen shot

Answer 10

thats not one of them either o.o

Answer 11

49

Answer 12

ohhh wait its a composite

Answer 13

3x^3 - 2x^2

plug in x=3, it's not 9.

Answer 14

its a composite function ~.~ I read it wrong.

Answer 15

when you have (g.f)(3)
you pluf 3 in f(x) first then the result that you get you plug it into g(x), so answer is 49

Answer 16

Oh it's gof(x)... very different to (g·f)(3).

g(f(3)) = g(3*3 - 2) =

g(7) = 7^2

Answer 17

what if you have (fof)(0)

and f(x)=x^2-1

wouldn't the outcome still be 0?

Answer 18

-1

Answer 19

ooooooooooo i get it now.

Answer 20

@agent0smith so was my answer right?

Answer 21

so its just f(f(x))

Answer 22

^stop posting answers especially when they're wrong @sensuelle1985

f(f(x)) = f(0^2-1) =

f(-1) = (-1)^2 - 1 = 0

Answer 23

yeah gotta plug -1 into the equation again

Answer 24

@agent0smith i meant to put 0 its, an error and as far as the other question the answer that I have found was part of her choices!

Answer 25

Thank you you guys :3

Answer 26

and @hkmiu yes you have to put -1 in the equation

Answer 27

@sensuelle1985 this wasn't though:

You've already chosen the best response. Medals 0
9
25 minutes ago

^ posting answers is not helpful. Posting wrong answers is really unhelpful.

Answer 28

no i haven't chose any answer as best response! and thats not the point as we are here to help each other out, so cut it Mr smart!!!

Answer 29

^don't post answers without showing any working, it's actually part of the site's TOS.

Posting an answer, even if correct, doesn't help someone learn.

Answer 30

thank you for your input! will do for now on