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

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==Solution==
 
==Solution==
We know that our answer must have an odd exponent in order for it to not be a square.  We can rewrite <math>4^{2019}</math> as <math>2^{4028}</math>, so our answer must be <math>\boxed{\textbf{(B) }2^{2017}}</math>
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We know that our answer must have an odd exponent in order for it to not be a square.  We can rewrite <math>4^{2019}</math> as <math>2^{4038}</math>, so our answer must be <math>\boxed{\textbf{(B) }2^{2017}}</math>
  
 
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{{AMC8 box|year=2016|num-b=6|num-a=8}}
 
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Revision as of 13:35, 23 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. We can rewrite $4^{2019}$ as $2^{4038}$, 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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All AJHSME/AMC 8 Problems and Solutions

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