<p>when you are taking the partial derivative of the Lagrangian wrt l you are taking the other variables as constants, so they are derived away. You cannot do this with f(k,l) as this is a function with a l input</p>
<p>the same applies to the partial derivative of the Lagrangian wrt k</p>
<p>refer back to the rules of partial differentiation</p>

CC BY-SA 4.0
2023-10-28T10:52:44.513Z
2023-10-28T10:52:44.513Z
AscendedYield
<p><a href="https://i.sstatic.net/VkumF.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/VkumF.png" alt="" /></a></p>
<p>Guys in the following optimisation problem why are we not considering the partial derivate of K and L in the Lagrangian in the first two equations</p>

<macroeconomics><microeconomics><mathematical-economics>
Cost Minimization
user205152
# Cost Minimization

(Asked by: username_0 on 2023-10-27)

[![](https://i.sstatic.net/VkumF.png)](https://i.sstatic.net/VkumF.png)

Guys in the following optimisation problem why are we not considering the partial derivate of K and L in the Lagrangian in the first two equations

**Tags:** macroeconomics, microeconomics, mathematical-economics


---

## 1 answers

### Answer by username_1 on 2023-10-28. Score: 1

when you are taking the partial derivative of the Lagrangian wrt l you are taking the other variables as constants, so they are derived away. You cannot do this with f(k,l) as this is a function with a l input

the same applies to the partial derivative of the Lagrangian wrt k

refer back to the rules of partial differentiation


---

