Question

Consider a parabola with its axis along the Y-axis. The corresponding function is __-

• A. neither one-one nor onto
• B. many-one and onto
• C. one-one but not onto
• D. one-one and onto

Answer 1

The correct option is A

neither one-one nor onto

From the graph , it can be seen that for every value of y there are 2 corresponding values of x . So the given function is not one-one.

Also f(x) assumes only non-negative values. So, no negative real number in R(co-domain) has its pre-image in domain R.

Therefore, f is not onto as well.