Subtraction in ℤ/pℤ or in ℤ/pℤ[x]

11.8.3 Subtraction in ℤ/pℤ or in ℤ/pℤ[x]

The - operator subtracts two integers in ℤ/pℤ or two polynomials in ℤ/pℤ[x]. (See also Section 7.3.2.) For polynomial expressions, use the normal command to simplify.

Examples

For integers in ℤ/pℤ:

31%13-10%13

⎛
⎝

−5

⎞
⎠

%13

For polynomials with coefficients in ℤ/pℤ:

normal((11*x+5)%13-(8*x+6)%13)

or:

normal(11%13*x+5%13-(8%13*x+6%13))

⎛
⎝

3%13

⎞
⎠

⎛
⎝

−1

⎞
⎠

%13