So the derivative of e to the x, which is just e to the x, times the second expression, not taking its derivative, so times cosine of x plus the first expression, not taking its derivative. So e to the x times the derivative of the second expression. So times the derivative of cosine of x, is negative sine, negative sine of x. And it might be a little bit confusing because e to the x is its own derivative, but this right over here, you can view this as this was the derivative of e to the x, which happens to be e to the x. That's what's exciting about that expression or that function. And then this is just e to the x without taking its derivative. They're of course the same thing.