164k views
1 vote
Find the relative maximum value of f(x, y) subject to the constraint?

User Ysearka
by
8.6k points

1 Answer

4 votes

Final answer:

To find the relative maximum value of f(x, y) subject to a constraint, identify the constraint equation and express f in terms of a single variable. Find the critical points of f(x) and evaluate f(x) at each critical point and the endpoints of the constraint interval.

Step-by-step explanation:

Relative Maximum Value of f(x, y) Subject to Constraint

To find the relative maximum value of f(x, y) subject to a constraint, follow these steps:

  1. Identify the constraint equation.
  2. Use the constraint equation to eliminate one variable in the function f(x, y) and express f in terms of a single variable.
  3. Find the critical points of f(x) by taking the derivative and setting it equal to zero.
  4. Evaluate f(x) at each critical point to determine the maximum value.

Remember to check for endpoints of the constraint interval as well.

For example, if the constraint equation is x + y = 10 and the function is f(x, y) = x^2 + y^2, you can solve the constraint equation for y in terms of x to get y = 10 - x. Substitute this expression into f(x, y) to get f(x) = x^2 + (10 - x)^2. Take the derivative, set it equal to zero, and find the x values of the critical points. Evaluate f(x) at these critical points and the endpoints of the constraint interval to determine the relative maximum value.

User Mike Hennessy
by
8.0k points