(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the last digit of [tex]7^{123} [/tex]

2. Relevant equations

3. The attempt at a solution

[tex]7^{123} \equiv x(mod 10)[/tex]

123=12*10+3 Now, since in Z_10

[tex]7^{120 }\equiv 1 (mod 10)=> 7^{123} \equiv 7^3=343 mod 10=>343(mod 10)=3[/tex]

SO would the last digit be 3????

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: FInd the last digit?

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