public void Sin_Constant()
        {
            PolynomialTerm term = Math.PI / 2;

            PolynomialTerm.Sin(term).AssertIsEqualTo(1);
        }
 public void Sin_Variable()
 {
     PolynomialTerm.Sin(Term.a).AssertIsEqualTo(IndeterminateExpression.Sin('a'));
 }