Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: [ Ссылка ]
The Lagrange multiplier technique is how we take advantage of the observation made in the last video, that the solution to a constrained optimization problem occurs when the contour lines of the function being maximized are tangent to the constraint curve.
![](https://i.ytimg.com/vi/yuqB-d5MjZA/maxresdefault.jpg)