public void DerivativeTest3()
{
// cot(2x)
Number num = new Number(2);
Variable x = new Variable("x");
Mul mul = new Mul(num, x);
IExpression exp = new Cot(mul);
IExpression deriv = exp.Differentiate();
Assert.AreEqual("-((2 * 1) / (sin(2 * x) ^ 2))", deriv.ToString());
num.Value = 3;
Assert.AreEqual("cot(3 * x)", exp.ToString());
Assert.AreEqual("-((2 * 1) / (sin(2 * x) ^ 2))", deriv.ToString());
}
public void CotDerivativeTest3()
{
// cot(2x)
var num = new Number(2);
var x = new Variable("x");
var mul = new Mul(num, x);
var exp = new Cot(mul);
var deriv = Differentiate(exp);
Assert.Equal("-((2 * 1) / (sin(2 * x) ^ 2))", deriv.ToString());
num.Value = 3;
Assert.Equal("cot(3 * x)", exp.ToString());
Assert.Equal("-((2 * 1) / (sin(2 * x) ^ 2))", deriv.ToString());
}