Difference between revisions of "2016 AMC 8 Problems/Problem 7"

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==Solution==
 
==Solution==
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We know that our answer must have an odd exponent in order for it to not be a square.  Because <math>4</math> is a perfect square, <math>4^{2019}</math> is also a perfect square, so our answer must be <math>\boxed{\textbf{(B) }2^{2017}}</math>.
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Revision as of 21:29, 27 November 2016

Which of the following numbers is not a perfect square?

$\textbf{(A) }1^{2016}\qquad\textbf{(B) }2^{2017}\qquad\textbf{(C) }3^{2018}\qquad\textbf{(D) }4^{2019}\qquad \textbf{(E) }5^{2020}$

Solution

We know that our answer must have an odd exponent in order for it to not be a square. Because $4$ is a perfect square, $4^{2019}$ is also a perfect square, so our answer must be $\boxed{\textbf{(B) }2^{2017}}$.

2016 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 6
Followed by
Problem 8
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