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Find the second derivative of 2x^3-3y^2=8​

User Uzilan
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1 Answer

5 votes

Answer:


(d^2y)/(dx^2)=(x(2y-x^3))/(y^3)

Explanation:

Find the first implicit derivative using implicit differentiation


2x^3-3y^2=8\\\\6x^2-6y(dy)/(dx)=0\\ \\-6y(dy)/(dx)=-6x^2\\ \\(dy)/(dx)=(x^2)/(y)

Use the substitution of dy/dx to find the second derivative (d²y/dx²)


(d^2y)/(dx^2)=((y)(2x)-(x^2)((dy)/(dx)))/(y^2)\\ \\(d^2y)/(dx^2)=(2xy-(x^2)((x^2)/(y)))/(y^2)\\\\(d^2y)/(dx^2)=(2xy-(x^4)/(y))/(y^2)\\\\(d^2y)/(dx^2)=(x(2y-x^3))/(y^3)

User Martin Kleppmann
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