Q. Using implicit differentiation, find dxdy.xy=−4+xy3
Apply Chain and Product Rule: First, we need to differentiate both sides of the equation with respect to x. The equation is xy=−4+xy3. We will apply the chain rule and product rule where necessary.
Differentiate Left Side: Differentiate the left side with respect to x. The left side is xy, which is (xy)21. Using the chain rule and product rule, we get 21(xy)−21×(xdxdy+y).
Differentiate Right Side: Differentiate the right side with respect to x. The right side is −4+xy3. The derivative of −4 is 0, and using the product rule for xy3, we get y3+3xy2dxdy.
Equate Derivatives: Now we equate the derivatives from both sides: (21)(xy)−21∗(xdxdy+y)=0+y3+3xy2dxdy.
Simplify Equation: Simplify the equation by multiplying both sides by 2(xy)1/2 to get rid of the fraction and the square root: xdxdy+y=2(xy)1/2(y3+3xy2dxdy).
Expand Right Side: Expand the right side of the equation: xdxdy+y=2y3(xy)21+6x2y2dxdy.
Group Terms: Group the terms with dxdy on one side and the rest on the other side: xdxdy−6x2y2dxdy=2y3xy−y.
Factor Out: Factor out (dxdy) on the left side: (dxdy)(x−6x2y2)=2y3(xy)21−y.
Solve for dxdy: Solve for dxdy by dividing both sides by (x−6x2y2): dxdy=x−6x2y22y3(xy)21−y.
Final Simplification: Simplify the expression for dxdy if possible. However, in this case, the expression is already in its simplest form.
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