Question

Which function is a quadratic function?
f(x) = 2x2
g(x) = 5x3
k(x) = –x
b(x) = –9x4

Answer 1

F(x) is the only quadratic function here. Any term with a degree of 2 starting the equation is a quadratic. 

Answer 2

The function f(x)=$2x^2$ will be a quadratic function as its degree is 2.

what is a quadratic function?

A quadratic function is defined as the polynomial having a degree equal to 2 that is the power of the variable should be 2 so that it will be a quadratic fuction.

here we have the functions.

$f(x) = 2x^2$

$g(x) = 5x^3$

$k(x) = –x$

$b(x) = -9x^4$

We can clearly see that the function $f(x) = 2x^2$ has the degree of 2 so it is a quadratic function.

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