1. f(x)=x^3+5

Question

does f(x) have an inverse? if so, find the inverse and decide if it is a function.

2. if f(x)= 3x+1 and g(x)= x^2-1, find
(f∙ g)(2)

3. if f(x)= (2x)^2, find f(-4)

thank you :)

Answer 1

1. let y = x^3 + 5
inverse is x = y^3 + 5
y^3 = x-5
y = (x-5)^(1/3)
yes , it is a function

2. (f∙ g)(2) = f(g(2))
= f(3)
= 10

3. Come on, you can do this!