Manish writes the functions g(x) = ^3 sqrt - x - 72 and h(x) = -(x+72)^3 Which pair of expressions could Manish use to show that g(x) and h(x) are inverse functions?

Here we want to find the expressions we need to use to see if the functions g(x) and h(x) are inverses of each other.

The correct option is the last one, counting from the top.

∛((x + 72)^3) - 72  and -(∛(-x) - 72 + 72)^3

Two functions f(x) and g(x) are inverses if:

f( g(x) ) = x

g( f(x) ) = x

In this case, we have the functions:

g(x) = ∛(-x) - 72

h(x) =  -(x + 72)^3

Then the expressions we need to check are:

g( h(x) ) = ∛(-h(x)) - 72 = ∛(+(x + 72)^3) - 72 = (x + 72) - 72 = x

h( g(x) ) = -(g(x) + 72)^3 = -(∛(-x) - 72 + 72)^3 = -(∛(-x) )^3 = x

So we found that the two expressions needed are:

∛((x + 72)^3) - 72  and -(∛(-x) - 72 + 72)^3

Then the correct option is the last one, counting from the top.

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