Question

Which represents a quadratic function? f(x) = 2x3 + 2x2 – 4 f(x) = –7x2 – x + 2 f(x) = –3x + 2 f(x) = 0x2 + 3x – 3

Answer 1

Answer:

Second option: $f(x) =-7x^2 -x + 2$

Step-by-step explanation:

A quadratic function has the form:

$f(x)=ax^2+bx+c$

(Where $a\neq0$)

You can observe that the highest exponent of a quadratic function is 2.

Then, let's check which of the options shows a quadratic function:

1) $f(x) = 2x^3 + 2x^2 - 4$

Its highest exponent is 3, then this is not a quadratic function.

2) $f(x) =-7x^2 -x + 2$

Its highest exponent is 2 and $a\neq0$, then this is a quadratic function.

3) $f(x) = -3x + 2$

Its highest exponent is 1, then this is not a quadratic function.

4) $f(x) =0x^2+3x-3$

You can observe that $a=0$, then this is not a quadratic function.