Function y=g(x)=2x^3-7

Question

Answer 1

A) y = 2x³ - 7

2x³ = y + 7

x³ = (y + 7)/2

x = ³√[(y + 7)/2]

g^-1(x) = ³√[(x + 7)/2]

g(g^-1(x)) = 2(³√[(x + 7)/2])³ -7 = 2√[(x + 7)/2) - 7 = x + 7 - 7 = x

g^-1(g(x)) = ³√[2x³ - 7 + 7)/2] = ³√(2x³/2) = ³(x³) = x

The rest is on you. Go!