How do you find dy/dx using implicit differentiation for the equation x² + 8xy + y² = 8?

To find dy/dx using implicit differentiation for the equation x² + 8xy + y² = 8, follow these steps:

  1. Start with the given equation:

    x² + 8xy + y² = 8

  2. Differentiate both sides with respect to x. Remember, when you differentiate terms involving y, you will need to apply the chain rule and include dy/dx:

    The derivative of is 2x.

    The derivative of 8xy uses the product rule:

    If u = 8x and v = y, then d(uv)/dx = u(dv/dx) + v(du/dx), resulting in:

    8y + 8x(dy/dx)

    The derivative of is 2y(dy/dx).

  3. Now put it all together:

    2x + (8y + 8x(dy/dx)) + 2y(dy/dx) = 0

  4. Rearranging the equation, isolate all terms that contain dy/dx:

    8x(dy/dx) + 2y(dy/dx) = -2x – 8y

  5. Factor out dy/dx:

    dy/dx (8x + 2y) = -2x – 8y

  6. Now, solve for dy/dx:

    dy/dx = \frac{-2x – 8y}{8x + 2y}

So, the derivative of y with respect to x, dy/dx, is given by:

dy/dx = \frac{-2x – 8y}{8x + 2y}

This result tells you how y changes with respect to x at any point on the curve defined by the given equation.

Leave a Comment