public void DerivativeTest3()
{
// x ^ 3
Variable x = new Variable("x");
Number num1 = new Number(3);
IExpression exp = new Pow(x, num1);
IExpression deriv = exp.Differentiate();
Assert.AreEqual("1 * (3 * (x ^ (3 - 1)))", deriv.ToString());
num1.Value = 4;
Assert.AreEqual("x ^ 4", exp.ToString());
Assert.AreEqual("1 * (3 * (x ^ (3 - 1)))", deriv.ToString());
// 2 ^ (3x)
Number num2 = new Number(2);
num1 = new Number(3);
Mul mul = new Mul(num1, x.Clone());
exp = new Pow(num2, mul);
deriv = exp.Differentiate();
Assert.AreEqual("(ln(2) * (2 ^ (3 * x))) * (3 * 1)", deriv.ToString());
num1.Value = 4;
Assert.AreEqual("2 ^ (4 * x)", exp.ToString());
Assert.AreEqual("(ln(2) * (2 ^ (3 * x))) * (3 * 1)", deriv.ToString());
}
public void PowDerivativeTest3()
{
// x ^ 3
var x = new Variable("x");
var num1 = new Number(3);
var exp = new Pow(x, num1);
var deriv = Differentiate(exp);
Assert.Equal("1 * 3 * (x ^ (3 - 1))", deriv.ToString());
num1.Value = 4;
Assert.Equal("x ^ 4", exp.ToString());
Assert.Equal("1 * 3 * (x ^ (3 - 1))", deriv.ToString());
// 2 ^ (3x)
var num2 = new Number(2);
num1 = new Number(3);
var mul = new Mul(num1, x.Clone());
exp = new Pow(num2, mul);
deriv = Differentiate(exp);
Assert.Equal("ln(2) * (2 ^ (3 * x)) * 3 * 1", deriv.ToString());
num1.Value = 4;
Assert.Equal("2 ^ (4 * x)", exp.ToString());
Assert.Equal("ln(2) * (2 ^ (3 * x)) * 3 * 1", deriv.ToString());
}