Assignment week 3.
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Computing modulo an irreducible polynomial f in Q[x].
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1) Write a procedure
  m := proc(a,b, f,x)

that calculates the product of a*b mod f.
(just multiply a and b and use rem).



2) Then write a procedure
  q := proc(a,b, f,x)

that calculates a/b mod f.
(use:  gcdex(b,f,1,x,'s','t') in your procedure
 to solve the equation:  s*b + t*f = 1.
 Use this to find 1/b mod f.
 Then compute a/b mod f).