To find : Formula for g-1.
Step 1: Substitute y=gx⇒ y=1-x33⇒ y3=1-x3 ⇒ x=1-y33.
Step 2: Interchange the positions of x and y. We get y=1-x33.
Conclusion: Thus, g-1x=1-x33.
Note: Functions g and g-1 are the same.
The blue-colored graph represents both the functions f and f-1. As you can see from the above figure, the given graph is symmetrical about the line y=x.