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Find $\dfrac{dy}{dx}$, where $x^3-3xy^3+x^2+y^2+7=0$ How am I supposed to extract $y$ as a function of $x$ fom that equation? Thank you!

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    Is this from a chapter on implicit differentiation by any chance?2017-01-05
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    I don't know exactly where it is from. It is from an exam...so can't tell!2017-01-05
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    Okay let me rephrase: you have to use implicit differentiation.2017-01-05
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    These downvoters really annoy me: it is obvious that the OP doesn't know that the problem is solved with implicit differentiation, so he is painfully and mistakenly looking to express $y$ as a function of $x$. Mathematicians are supposed to be intelligent and to be able to read between the lines, but I don't see this in all this downvoting.2017-01-05
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    @DenisNichita: So far you have asked 16 questions but only accepted 2 answers. On behalf of the Math.SE users, I apologize for us not being up to your level of excellence.2017-01-07

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assuming that we have $$y=y(x)$$ then we get by differentiating with respect to $x$ $$3x^2-3y^3-3x\cdot 3y^2\cdot y'+2x+2y\cdot y'=0$$

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    Where did you get $-3x3y^2y'$ and $2yy'$?2017-01-05
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    @DenisNichita As I had said before two times, implicit differentiation2017-01-05