Function compostions
posted by Soly on .
Sorry I had to repost, I left somethings out.
Can you please check my answers?
For the given functions f and g, find the indicated composition.
5. f(x)=7x+9, g(x)=2x1
Find (f *g)(x)
I got 14x+2
For the given functions f and g, find the indicated composition.
8. f(x)=5x+3, g(x)=6x+3
(g * f)(x)
I got 30x+18
Find functions f and g so that h(x)= (f *g)(x)
12. h(x)= 1/(x^22)
I got (f)=1/x, g(x)=x^22
14. h(x)=(2x+19)^5
I got f(x)x^5, g(x)=2x+19

If your f*g(x) means f(g(x)), then for problem #5,
f[g(x)] = 7(2x1) + 9 = 14 x + 2
For problem #12, there may be more than one combination of f and g that result in
f[g(x)] = 1/(x^22). The two functions you listed work fine.