Question

Which of the following functions is even?

Answer 1

Answer: Choice C

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

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Explanation:

If all the exponents are even, then the polynomial function is even.

• Choice A has a mix of even and odd exponents here, so choice A is neither even nor odd. We can rule this out.
• Choice B is the same story as choice A. So we can rule that out as well.
• Choice C has all of its exponents even. Therefore function C is an even function, and it's the final answer.
• Choice D is the same story as choice A. The only difference is the leading coefficient is positive.