102k views
4 votes
Use Lagrange multipliers to find the maximum and minimum values of f(x,y,z)=x2-8y+10z2 subject to the constraint x2+y2+z2=1

1 Answer

5 votes

Final answer:

To find the maximum and minimum values of f(x, y, z) = x^2 - 8y + 10z^2 subject to x^2 + y^2 + z^2 = 1, use Lagrange multipliers.

Step-by-step explanation:

To find the maximum and minimum values of the function f(x, y, z) = x^2 - 8y + 10z^2 subject to the constraint x^2 + y^2 + z^2 = 1, we can use Lagrange multipliers.

  1. Write down the objective function and the constraint equation:
  2. f(x, y, z) = x^2 - 8y + 10z^2
  3. g(x, y, z) = x^2 + y^2 + z^2 - 1
  4. Compute the gradient of both functions:
  5. ∇f(x, y, z) = (2x, -8, 20z)
  6. ∇g(x, y, z) = (2x, 2y, 2z)
  7. Set up the system of equations:
  8. 2x = λ(2x), -8 = λ(2y), 20z = λ(2z), x^2 + y^2 + z^2 = 1
  9. Solve the system of equations to find the values of x, y, z, and λ.
  10. Substitute the values of x, y, and z into the objective function to find the maximum and minimum values of f(x, y, z).
User Alexxjk
by
8.3k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.