I dont know the answer:( Can someone please help?

Question

Let f(x) = x^2 - 1 and g(x) = 2x. What is (g ? f)(4), or g(f(4))?

 

 

Let f(x) = 3x and g(x) = x^2 + 2. What is (g ? f)(-3), or g(f(-3))?

Answer 1

(g o f)(4) = g(f(4)) = g(15) = 2(15) = 30

 

(g o f)(-3) = g(f(-3)) = g(-9) = (-9)² + 2 = 81 + 2 = 83.

 

Are you not able to get the special symbols, or do you not want to use them?