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I have a problem here thats been bugging me. I was wondering if anyone can give insight into where I'm going wrong

implicit differentiation problem

1) (x^2+y^2)/(x+y)=xy-2

find derivitive (dy/dx) at point (-1, -1)

I know the basic premise. I used the quotient rule to find the derivative of the fraction. Im confused about the resulting fraction though. Once you find the derivative of the fraction, what should you do about the denominator ( which will be (x+y)^2 ). do you multiply each side by it? ( which would remove it from the left hand side, but add it to the right hand side). I've also tried moving the "xy" from the right hand side to the left side, but it seems to make the problem more confusing. Once I find the derivative (dy/dx) I know you just plug in the (x,y) value, so thats no problem.

If anyone can help, I would appreciate it greatly!!!

UPDATE!!!!

I think I may have made the problem easier.. still gonna try it out though. What if you got rid of the fraction on the left hand side from the beginning? Would that make it easier?

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# Homework Help: Question Involving implicit Differentiation

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