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Lagrange multiplier between a sphere and a plane.

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Final answer:

In physics, Lagrange multipliers are mathematical tools used to find the maximum or minimum value of a function subject to a constraint. In the case of a sphere and a plane, we can use Lagrange multipliers to find the point(s) on the sphere that are tangent to the plane. By setting up a system of equations involving the equations of the sphere, the plane, and a constraint, we can solve for the coordinates of the point(s) of tangency.

Step-by-step explanation:

Lagrange multipliers between a sphere and a plane

In physics, Lagrange multipliers are mathematical tools used to find the maximum or minimum value of a function subject to a constraint. In the case of a sphere and a plane, we can use Lagrange multipliers to find the point(s) on the sphere that are tangent to the plane. This is done by setting up a system of equations that involves the equations of the sphere and the plane, as well as an additional equation that represents the constraint. By solving these equations, we can determine the coordinates of the point(s) of tangency.

Example:

Consider a sphere with radius 2 centered at the origin and a plane described by the equation x + y + z = 5. To find the point(s) on the sphere that are tangent to the plane, we can set up the following system of equations:

  1. Equation of the sphere: x^2 + y^2 + z^2 = 4
  2. Equation of the plane: x + y + z = 5
  3. Constraint equation: let's say we want to find the point(s) on the sphere that are tangent to the plane, which means the distance between the center of the sphere and the plane is equal to the radius of the sphere. This can be represented by the equation sqrt(x^2 + y^2 + z^2) - 2 = 0
  4. By setting up the Lagrange multiplier equations:
  • ∂f/∂x = ∂g1/∂x + λ * ∂h/∂x = 0
  • ∂f/∂y = ∂g1/∂y + λ * ∂h/∂y = 0
  • ∂f/∂z = ∂g1/∂z + λ * ∂h/∂z = 0
  • g1(x, y, z) = x + y + z - 5 = 0
  • h(x, y, z) = sqrt(x^2 + y^2 + z^2) - 2 = 0
  • where f(x, y, z) = 0 represents the function to be optimized (in this case, we want to find the point(s) on the sphere that are tangent to the plane) and λ is the Lagrange multiplier.
  • Solve the system of equations to find the coordinates of the point(s) of tangency.
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