Question

Which of the following functions has an inverse that is not a function?

y = x
y = 2x + 1
y = x²

Answer 1

y=x^2 has an inverse but it is not a function

Explanation:

y = x

y=x has an inverse function. y=x is the equation of a line. All line has an inverse function and it is also a function

y = 2x + 1 is the equation of a line.

All line has an inverse function and it is also a function

y = x^2 is the equation of a quadratic

Quadratic equation has an inverse but it does not pass vertical line test.

Hence it is not a function

Answer 2

y = x² has an inverse that is not a function