Question

If f(x) = 2x and g(x) = 5x, calculate f(g(x)).
@cgreenwade2000

Answer 1

This one is a little different. Instead of multiplying the two together here, you want to substitute the entire expression of g into f.

Answer 2

so 2x * 5x*2x ?

Answer 3

For example: f(x) = 25x
g(x) = 4x^2

so f(g(x)) = 25(4x^2) everywhere here there was an x I substituted it out with g(x)

Answer 4

Not quite.

Answer 5

oh, so 2x(5x)

Answer 6

Anywhere you see and x in f(x), you are going to take it out and put the entire expression of G(x) instead

Answer 7

wouldnt it still be 10x^2

Answer 8

No, try again

Answer 9

so ((2x)*5x *5x)

Answer 10

Anywhere you see and x in f(x), you are going to take it out and put the entire expression of G(x) instead

Answer 11

i tried

Answer 12

What does f(x) equal?

Answer 13

2x

Answer 14

Anywhere you see an x in f(x), you are going to take it out and put the entire expression of G(x) instead

Answer 15

Take out the x in f(x) and put in what g(x) is equal to there.

Answer 16

It should look like this

2(whatever g(x) is)

Answer 17

so (2)(5x)

Answer 18

Yeah, thats it. Now you simplify that and you have f(g(x))

Similarly g(f(x)) is just putting in f(x) for every x in g

Answer 19

either way it still 10x

Answer 20

Yep. It won't always be like that, but in this case it is.

Answer 21

thank you,