a.) Show that the DE is exact and find a general solution
2y - y^2sec^2(xy^2)+[2x-2xysec^2(xy^2)]y' = 0
b.) Verify that the equation is not exact. Multiply byintegrating factor u(x, y) = x and show that resulting equation isexact, then find a general solution.
(3xy+y^2) + (x^2 + xy)dy/dx = 0
c.) Verify that the equation is not exact. Multiply byintegrating factor u(x, y) = xy and show that resulting equation isexact, then find a general solution.
(-xysinx + 2y cosx) + 2xcosx(dy/dx) = 0
