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6.34.11  Inverse in ℤ/pℤ: inv inverse /

The inv command finds the inverse of an integer in ℤ/pℤ.
inverse is a synonym for inv.

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).


Example.
Input:

inv(3%13)

Output:


−4
%13

Indeed 3×−4=−12=1 (mod 13).
You can also find the reciprocal using division: Input:

1/(3%13)

Output:


−4
%13

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