College Algebra (Inverse)

Question

Determine if the functions are inverses of each other:

1) f(x)=(x+4)^3 and g(x)= ∛x+1 -4

2) f(x)= 5x+9 and g(x)= x+9/5

Answer 1

switch x and y or f(x) to get x=(y+4)^3 take cube roots to get y+4 = x^1/3 or y=g(x) = x^1/3 -4

they aren't inverses, that "1" throws it off, almost though

x=5y+9, solve for y. y =g(x) = x/5 -9/5. not inverses. need x/5, not x