Solving Multivariable Problems Using Lagrange Multipliers

In summary, the conversation discusses three problems, including the Cobb-Douglas production function, using Lagrange multipliers, and a change of variable for double integrals. The first problem involves finding the dependence of output Q on capital K when labor L is held constant. The second problem involves finding the dependence of output Q on labor L when capital K is held constant. The third problem involves using a change of variable to solve a double integral. The conversation also provides helpful resources and examples for solving the problems.
  • #1
Vanrichten
12
0
Ok the first problem is The output Q of an economic system subject to two inputs, such as labor L and capital K, soften modeled by the Cobb-Douglas production function Q(L;K) = cLaKb, where a; b and c
are positive real numbers. When a+b = 1, the case is called constant returns to scale. Suppose
a = 1
3 , b = 2
3 and c = 40.

A) If L is held constant at L = 10, write the function that gives the dependence of Q on K.
B) If K is held constant at K = 15, write the function that gives the dependence of Q on L

Does this look ok Name: View attachment 1681
Next I have this problem View attachment 1682

I'm pretty sure you have to use Lagrange multipliers on this one I know you first need to take partial derivatives of the function then set up the scalar equations involving lamba, I know that much but I'm stuck there.

The third problem I have is this View attachment 1683For this problem I graphed it out and you can see that there are two sets of parallel lines and the region is rectangular so I think you can use a change of variable. I tried v=y and u=2x+y but it didn't work
 

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  • #3
Prove It said:
Have a read of the parallelogram problem here to help you with 14.

Double integral change of variable examples - Math Insight

I think I got it. Could you verifiy I have the correct change of variable now,

I got x = (u-v)/3 and y = (4u-v)/3
 
  • #4
For one possible way to solve problem 11, I recommend you read this thread:

http://mathhelpboards.com/questions-other-sites-52/emwhys-question-yahoo-questions-regarding-finding-extrema-given-region-7266.html
 

Related to Solving Multivariable Problems Using Lagrange Multipliers

1. What are multivariable problems?

Multivariable problems are mathematical problems that involve multiple variables, or unknown quantities. These problems often require the use of advanced mathematical tools and techniques to solve.

2. How are multivariable problems different from single variable problems?

In single variable problems, there is only one unknown quantity, or variable, that needs to be solved for. In multivariable problems, there are multiple unknown quantities that need to be determined simultaneously. This adds an extra layer of complexity to the problem.

3. What are some real-world applications of multivariable problems?

Multivariable problems are commonly used in fields such as physics, engineering, economics, and statistics. They can be used to model and solve problems involving multiple variables, such as predicting the trajectory of a projectile or optimizing a manufacturing process.

4. What are some techniques used to solve multivariable problems?

Some common techniques used to solve multivariable problems include substitution, elimination, and graphing. These methods involve manipulating equations and using algebraic and geometric principles to solve for the unknown variables.

5. How can I improve my skills in solving multivariable problems?

Practice is key to improving your skills in solving multivariable problems. It is important to have a strong foundation in algebra and calculus, as well as a good understanding of the concepts and principles involved in multivariable problems. Working through practice problems and seeking help when needed can also aid in improving your skills.

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