Please help with this composite function

[khris le]

This is the question If f(x) = 2x -1 and f(g0) = 2x squared+ 4 find fg(x)
My answer is 7+2x squared yet the answer from the solution page is 2x squared +3 and I don't understand why.

 

[Otis]

composite function … If f(x) = 2x-1 and f(g0) = 2x squared +4

find fg(x)

Hello khris. The typed notation for composite functions is (fog)(x). Is that what you meant, instead of fg(x)?

(The name "fg" is for the product of functions f and g, not a composition.)

Also, I'm not sure what you mean by f(g0).

PS: We use the caret symbol ^ to show exponents, like this: 2x^2.



[imath]\;[/imath]

 

[Otis]

There are also other notations, for both the product of functions and a composition of functions (as Jeff mentioned in your other thread).

Using an asterisk for the multiplication sign:

(f*g)(x) means the same as f(x)*g(x)

f(g(x)) means the same as (fog)(x)

If you're not sure how to correct your post, please post an image of the exercise. Cheers

?

[imath]\;[/imath]