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# am i allowed to do this......(C3 related) watch

1. I have a question which asked to me find the co-ordinates to the turning points of the equation: y= x/9+x^2

I diffrentiated it using the quotient rule, and ended up with:

9-x^2 / (9+x^2)^2 = 0

could I re-arrange it so that the bottom half of the division goes to the other side with the '0'. Therefore it would be '(9+x^2)^2 ' multiplied by zero? So after, would I end up with '9-x^2 = 0' ?
2. Certainly; in fact that's the only thing you can do. If you have a non-zero numerator, then no denominator could make the overall fraction equal to zero (except at infinity...)
3. yeah, that's what you're meant to do

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