Hello all, I am trying to solve a line integral: Find the value of \int -2y dx + x^2 dy over the circle x^2 + y^2 = 9 as you can see, this is a line integral, and I am trying to figure a quick way how it should be solved. I thought of converting coordinates to (sint,cost) which will end up as a trigonometric function which needs to be integrated, but I believe there is a much easier way which I am not sure about. Also, I am not sure what is the notation f(y) dx + g(x) dy stands for. Is it the same as [f(y) - i g(x)] dz? Thanks for any help.