[10000印刷√] dy/dx=x^2 y^2 1/2xy 697570-2xy dy-(x^2+y^2+1)dx=0

 2xy x 2 dy/dx 5 d/dx (x) 3 d/dx (y) = d/dx (9) ∴ (d/dx(y) = dy/dx), d/dx(x) = 1 2xy x 2 dy/dx 5(1) 3 dy/dx = d/dx (9) As "9" is a constant and the derivative of any