Thread: 2nd derivative

I've done this problem two different ways and have gotten two different answers. It's very long and one simple algebraic mistake messes up everything so i was wondering if someone could find the anwer: find the second derivative of (x^2)(y^2)-2x=3. Can you use the quotient rule to find it so if i did do it wrong i can see where i made the mistake? i got (2x^2y^4-2xy^2-1)/(x^4y^3) the first time and (2x^2+y^2-2xy-1)/(x^4y^3) the second. Also, how do i find the derivative of an equation implicitly. Explicity it's d(f(x),x) but i can't figure it out implicitly. I'd rather check my work that way instead of bothering you. Thanks alot

What? isnt the first derivative (-xy^2+1)/(x^2*y)? i put that in the calculator and it gives me the same answer....please reply

Originally Posted by jarny

What? isnt the first derivative (-xy^2+1)/(x^2*y)? i put that in the calculator and it gives me the same answer....please reply

yes, that is true

now differentiate again