You could say that this is the same thing as sine of x over cosine of x times one over cosine of x. And of course, this is tangent of x times secant of x. Secant of x. So you could say derivative of secant x is sine of x over cosine squared of x, or it is tangent of x times secant of x. So now let's do cosecant. So the derivative with respect to x of cosecant of x, well, that's the same thing as the derivative with respect to x of one over sine of x. Cosecant is one over sine of x. I remember that, because you think it's cosecant, maybe it's the reciprocal of cosine, but it's not, it's the opposite of what you would expect. Cosine's reciprocal isn't cosecant, it is secant. Once again, opposite of what you would expect.