We have the minus 2 or the negative 2 on the outside. Derivative of cosine of 2x is going to be 2 times negative sine of x. So the 2 times 2 is 4. The negative sine of x times the negative right there is a plus. The positive sign, so it's sine of 2x. So that's the numerator when you take the derivative. And the denominator, this is just an exercise in taking derivatives.