Question

Which statement best describes how to determine whether f(x) = x4 – x3 is an even function?

Answer 1

A function is even if it can be reflected across the y axis and map onto itself

basically f(x) is even if f(-x)=f(x)

easy way to test is to see if f(-x)=f(x)

$(-x)^4-(-x)^3=x^4-x^3$
$x^4-(-x^3)=x^4-x^3$
$x^4+x^3=x^4-x^3$
nope, not even

answer is A

Answer 2

For an even function  f(x) = f(-x)

So its option A