I'm assuming you meant "Find where
Is that correct? If so, what would be the first step?
Yes. Rather than do that problem for you, let me find the second derivative of y when .
Differentiating once, . Differentiating again, . Now, you can solve for y'':
You could, now, replace y' from the first derivative but typically, that is not necessary.
as i retry this... Im workin on finding the formula for dy/dx
and i got to here... 3x^2+[x(dy/dx) + y(dx/dx)]+2y=0
now, the stuff in the brackets.. how do I simplify that... in the first term can I 'cancel' the x leaving y in the numerator. but then that leaves the second term...
No, you can't cancel inside the brackets. The symbol is one symbol. It is not a fraction. However, the , so that simplifies a bit. Incidentally, I would agree with your differentiation except for the last term. You should use the chain rule on it thus:
Can you continue?