Answer ? - impicit differentiation

Question

Find dy/dx & d^2y/dx^2

y^2 - x^2 = 2

is the answer dy/dx=x/y; d^2y/dx^2=
y^2-x^2/y^2

Answer 1

2y(dy/dx) - 2x = 0
dy/dx = 2x/(2y) = x/y

y'' = (y(1) - x(y'))/y^2
= (y - x(x/y))/y^2
= (y^2 - x^2)/y^3

you had y^2 at the bottom of your y''
did you notice that there was a y in the denominator of your top?