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How to solve the following congruence using properties.

$2^{14}=x (mod 17) $

I got the answer 13 using manual calculation. Thank in advance.

Bill Dubuque
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1 Answers1

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Use fermat's little theorem, you only get $2^{16} \equiv 1 \space \mod 17$ It is not much use for this question.

So I just use $2^4 \equiv -1 \space \mod 17$ ,manual calculation like you.

$2^{14} \equiv (-1)^3 \times 2^2 \equiv -4 \equiv 13 \space \mod 17$

Abel Wong
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