What is the slope of the tangent line of x^2/(x-y^3) = C x2xy3=C, where C is an arbitrary constant, at (-2,1)(2,1)?

1 Answer
Jan 2, 2016

-3/232

Explanation:

Find the implicit derivative of the function.

Use the product rule.

((x-y^3)d/dx(x^2)-x^2d/dx(x-y^3))/(x-y^3)^2=0(xy3)ddx(x2)x2ddx(xy3)(xy3)2=0

Remember that differentiating a yy term will spit out a dy/dxdydx term thanks to the chain rule.

(2x(x-y^3)-x^2(1-3y^2dy/dx))/(x-y^3)^2=02x(xy3)x2(13y2dydx)(xy3)2=0

Plug in (-2,1)(2,1) for (x,y)(x,y) and solve for dy/dxdydx.

(2(-2)(-2-1^3)-(-2)^2(1-3(1)^2dy/dx))/(-2-1^3)^2=02(2)(213)(2)2(13(1)2dydx)(213)2=0

Notice that the denominator can be cancelled out. Continue simplification of numerator.

(-4)(-3)-(4)(-2)dy/dx=0(4)(3)(4)(2)dydx=0

12+8dy/dx=012+8dydx=0

dy/dx=-3/2dydx=32

The slope of the tangent line is -3/232.