1) (2x+3)^3 -6
Write
y = (2x+3)^3 - 6 add 6 to both sides
y + 6 = (2x+ 3)^3 take the cube root of each side
∛ (y + 6) = 2x + 3 subtract 3 from both sides
∛ ( y + 6) - 3 = 2x divide both sides by 2
[ ∛ ( y + 6) - 3 ] / 2 = x "swap" x and y
[ ∛ ( x + 6) - 3 ] / 2 = y = the inverse
Putting this into (2x+3)^3 -6 we get
( 2 [ ∛ ( x + 6) - 3 ] / 2 + 3)^3 - 6 =
( ∛ ( x + 6) - 3 + 3 )^3 - 6 =
x + 6 - 6 = x
And putting the original into the inverse
[ ∛ ( [ (2x+3)^3 -6 ] + 6) - 3 ] / 2 =
[ ∛ { (2x + 3)^3 - 3 ] / 2 =
[2x + 3 - 3 ] / 2 =
2x / 2 = x
So...they are inverses !!!!