Implicit Differentiation Problem

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SUMMARY

The discussion centers on the implicit differentiation of the equation y² - 2xy + x³ = 0. The correct derivative, derived using the product rule, is confirmed as dy/dx = (2y - 3x²) / (2y - 2x). Initial confusion arose from misapplying the derivative of the term -2xy, which requires the product rule. The participants collaboratively resolved the issue and confirmed the correct solution.

PREREQUISITES
  • Understanding of implicit differentiation
  • Familiarity with the product rule in calculus
  • Knowledge of basic algebraic manipulation
  • Experience with derivatives of multivariable functions
NEXT STEPS
  • Study the product rule in calculus for multivariable functions
  • Practice implicit differentiation with various equations
  • Explore advanced differentiation techniques, such as logarithmic differentiation
  • Utilize tools like Wolfram Alpha for verifying calculus solutions
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Students studying calculus, educators teaching differentiation techniques, and anyone seeking to improve their understanding of implicit differentiation and product rule applications.

James2
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1. Given that [itex]y^{2}-2xy+x^{3}=0[/itex], find [itex]\frac{dy}{dx}[/itex]



2. (no relevant equations other than the problem statement)



3. So, I solved it like this,
[itex]\frac{dy}{dx}y^{2}-2xy+x^{3}=0[/itex]


[itex]2y\frac{dy}{dx}-2+3x^{2}=0[/itex]

Solving for dy/dx I got...

[itex]\frac{dy}{dx}=\frac{-3x^{2}+2}{2y}[/itex]

However, wolfram alpha on my phone when I checked it said that the derivative of -2xy was -2y...? What I am asking is, if there are two variables in one term, the derivative is different?
 
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I think your problem here was with the middle term:

[itex][D(2xy)] = [2xD(y) + yD(2x)] = [2xy' + 2y][/itex]

This gave me a solution of:

[itex]y' = \frac{2y-3x^{2}}{2y-2x}[/itex]
 
Yeah, I figured that out shortly after posting. I asked a friend and he said that the problem was that I didn't use the product rule on -2xy. We got the same solution once we worked it out, thanks! Is there a way to mark this thread as solved or something?
 

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