Which represents a quadratic function?
f(x) = 2x^3 + 2x^2 – 4
f(x) = –7x^2 – x + 2
f(x) = –3x + 2
f(x) = 0x^2 + 3x – 3

Only function (2) is quadratic function.

Step-by-step explanation:

Quadratic function is a function which  involves the second  higher power of an unknown quantity or variable.

In general form, quadratic function is represented as, where a,b,c are real numbers and

Thus, from the given function

1)

Since it has highest degree 3 , so it cannot be a quadratic function.

2)

This is a quadratic function, as it of the form where

a = -7, b = -1 , c= 2 and

3)

No, it is not a quadratic function as the highest power is 1.

4)

We can rewrite the given function as , as 0 multiply with anything is zero. So, it is not a quadratic function as the highest power is 1.

Thus, only function (2) is quadratic function.