The inv or inverse command finds the inverse of an integer in ℤ/pℤ.
Since ℤ/pℤ is only a field if p is prime, the inverse is only guaranteed to exist if p is prime (and the integer is non-zero).
inv(3%13) |
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Indeed, 3·(−4)=−12≡ 1(mod 13 ).
You can also find the reciprocal using division:
1/(3%13) |
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