You can
put this solution on YOUR website! A) f(x)=x²
B) f(x)=x³
C) f(x)=x
In each case replace f(x) by y
A) y = x²
B) y = x³
C) y = x
Interchange the variables x and y
A) x = y²
B) x = y³
C) x = y
For each, ask the question "Is this equivalent to what it was before the variables were interchanged?
A) Is x = y² equivalent to y = x²? Answer: NO
B) Is x = y³ equivalent to y = x³? Answer: NO
C) Is x = y equivalent to y = x ? Answer: YES
So the answer is C) f(x)=x
Edwin