- #1
KatieLynn
- 65
- 0
Homework Statement
Show f and g are inverse functions or state that they are not.
f(x)= cube root of -8x-6 g(x)= -(x^3+6)/(8)
Homework Equations
You find inverses by plugging the equations into each other, if they are inverses then once you simplify the composed equation, it will equal x.
The Attempt at a Solution
cube root of {-8[-(x^3+6)/(8)]-6} I plugged g(x) into f(x) now I need to solve it, this is what I did but its not right because the answer should come out to be just x.
I multiplied everything by 8 to get it out of the denominator and simplified the numerator which left me with
cube root of {64x^3-432}
then I thought maybe you could pull out the 64 and x^3 from the cube root to get
4x times the cube root of {-432}
which is definitely not going to = x not matter what I do to it.
I feel a bit stupid for not being able to solve this because the solving is not supposed to be the challenge, the concept of what makes the functions of inverses is. I think I've just forgotten how to solve harder equations.