So if I integrate both sides, what am I going to get? So the antiderivative of cosine of y with respect to y, with respect to y is sine of y. And then the antiderivative of two with respect to y is two y. And that is going to be equal to, well the antiderivative of two x with respect to x is x squared. And we can't forget that we could say a different constant on either side, but it serves our purpose just to say plus c on one side. And so this is a general solution to the separable differential equation. And then we can find the particular one by substituting in, when x is equal to one, y is equal to zero.