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Use Lagrange multipliers to find the maximum area S of a rectangle inscribed in the ellipse: (x²)/(16) + (y²)/49 = 1.

User Bousof
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Final answer:

To find the maximum area of a rectangle inscribed in an ellipse using Lagrange multipliers, follow these steps: Set up the optimization problem, take partial derivatives, solve for the critical points, and evaluate the solutions.

Step-by-step explanation:

To find the maximum area of a rectangle inscribed in an ellipse using Lagrange multipliers, we need to set up the optimization problem and solve it.

Step 1: Set up the optimization problem

We need to maximize the area of the rectangle, which is given by A = 2xy, subject to the constraint of the ellipse equation: (x²)/(16) + (y²)/49 = 1. We introduce a Lagrange multiplier λ to incorporate the constraint into the objective function. So, the Lagrangian function is L = 2xy + λ((x²)/16 + (y²)/49 - 1).

Step 2: Take partial derivatives

Calculate the partial derivatives of the Lagrangian function with respect to x, y, and λ. Set them equal to zero to find the critical points.

Step 3: Solve for the critical points

Solve the system of equations obtained from equating the partial derivatives to zero to find the values of x, y, and λ.

Step 4: Evaluate the solutions

Plug the values of x, y, and λ into the objective function A = 2xy to find the maximum area.

User Swanliu
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