Patrick B. answered 12/03/20
Math and computer tutor/teacher
x^2 y + y^2 = x
first derivative:
x^2 * y' + 2x y + 2y y' = 1
x^2 * y' + 2y y' + 2xy = 1
y' (x^2 + 2y) + 2xy = 1
y' = (1 - 2xy)/(x^2+2y)
2nd derivative:
y'' = [(x^2+ 2y)(-2) (xy' + y) - (1-2xy)(2)(x+y')]/(x^2+2y)^2
= [ (-2) (x^2+2y)(xy' + y) + (1-2xy)(x+y')]/(x^2+2y)^2
where y' is given above in terms of x and y