So this should be equal to the limit, if L'Hopital's Rule applies here, we're not 100% sure yet. This should be equal to the limit as x approaches 0 of the derivative of that thing over the derivative of that thing. So what's the derivative of 2 cosine of x? Well, the derivative of cosine of x is negative sine of x. So it's negative 2 sine of x. And then the derivative of cosine of 2x is negative 2 sine of 2x. So we're going to have this negative cancel out with the negative on the negative 2 and then a 2 times a 2.