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Implicit differentiation mistake in solution

Here is a question to which my answer disagrees with that stated in the solution. I would be grateful if others could confirm that they agree with mine! :

Find the equation of the tangent to the curve below at the point (1,2)
x3+x2y+xy2+y3=15x^{3}+x^2y+xy^2+y^3=15


I arrive at: y=1117x+4517y = -\frac{11}{17}x+\frac{45}{17}
Original post by Sm0key
Here is a question to which my answer disagrees with that stated in the solution. I would be grateful if others could confirm that they agree with mine! :

Find the equation of the tangent to the curve below at the point (1,2)
x3+x2y+xy2+y3=15x^{3}+x^2y+xy^2+y^3=15


I arrive at: y=1117x+4517y = -\frac{11}{17}x+\frac{45}{17}


is the answer y= -11/17 y +35/17 ?
Reply 2
Original post by zetamcfc
is the answer y= -11/17 y +35/17 ?


No I definitely get 45/17 for the constant term
Original post by Sm0key
No I definitely get 45/17 for the constant term


Picture of your workings please :smile:
Reply 4
Original post by Sm0key
Here is a question to which my answer disagrees with that stated in the solution. I would be grateful if others could confirm that they agree with mine!


Agree with your answer.
Original post by Sm0key
No I definitely get 45/17 for the constant term


lol i'm such a idiot :lol: i also agree :biggrin:
Reply 6
Also arriving at y= -11x/17 + 45/17
Reply 7
Thanks all for the assistance.

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