Use the functions to answer the question.

f(x) = 4x – 1; g(x) = 5x^2

Which is equal to (f * g) (x)?

80x^2 – 40x + 5
20x^3 – 5x^2
5x^2 + 4x – 1
20x^2 – 1

Question

Use the functions to answer the question.

    f(x) = 4x – 1; g(x) = 5x^2

Which is equal to (f * g) (x)? 

       80x^2 – 40x + 5 
       20x^3 – 5x^2
       5x^2 + 4x – 1
       20x^2 – 1

anonymous · Answer

This is obviously composite functions, so (f º g)(x) = f(g(x)) = 4x - 1 = 4(5x^2) - 1 = 20x^2 - 1. So, the answer is D, the last one.

anonymous · Answer

Thank you so much for your help!

anonymous · Answer

You welcome, a medal would be nice if you are satisfied :).

anonymous · Answer

I already put your answer as the best response.

anonymous · Answer

Okay, thanks, :). Good luck with your homework/test/etc.

anonymous · Answer

Thank you!