Practice question · True or false
A congruence may be divided through by a factor only when that factor is coprime to the modulus.
Hints
- Try dividing by 2.
- Coprimality is exactly the condition.
Show the answer
True
Why
True. divided by 2 gives the false , because 2 shares a factor with the modulus. Where the factor is coprime the division is valid; otherwise the modulus must be divided too, giving .
Practise Modular Arithmetic
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