Heylo <3

I have the answer to the question, but I can't seem to quite get to it successfully.

Please & thank you =)

Let f(x)= x^5 and g(x)= 2x-3, Find (g o f)(x) and (g o f)'x

-Finding (g o f)(x) -->

f(x) = x^5

g(x^5)=2x^5-3

Which is the correct answer for part 1

-Finding (g o f)'(x) -->

g'(f(x))(f'(x))

g'(x^5)(5x^4)

10x^4 * 5x^4

= 50x^8

But the answer 10x^4