Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
Lagrange multiplier question, please help I continously get the imaginary # 5iradical 5 as olambda
surface is f(x,y,z) = x^2+2y^2z^2+4xy=250
compute coordinartes of every pt on surface at which the tangent plane is parallel to the plane
x2y+z=20
 one year ago
 one year ago
Lagrange multiplier question, please help I continously get the imaginary # 5iradical 5 as olambda surface is f(x,y,z) = x^2+2y^2z^2+4xy=250 compute coordinartes of every pt on surface at which the tangent plane is parallel to the plane x2y+z=20
 one year ago
 one year ago

This Question is Open

snadigBest ResponseYou've already chosen the best response.0
Hi! You haven't said how you approached to solve the problem. The way I did is like this: \[\nabla f = <(2x+4y),(4x+4y),(2z)>\] and \[\nabla g = <1,2,1>\] The equations are: \[\nabla f = \lambda \nabla g, g = c\] This gave me a the following matrix equation: \[\left[\begin{matrix}2 & 4 & 0 & 1 \\ 4 & 4 & 0 & 2\\ 0 & 0 & 2 & 1\\ 1 & 2 & 1 & 0\end{matrix}\right] \left[\begin{matrix}x \\ y \\z\\ \lambda \end{matrix}\right] = \left[ \begin{matrix}0 \\ 0 \\0\\ 20 \end{matrix}\right]\] The solution to this is: x = 7.5, y = 5, z = 2.5 and lambda = 5 Next, I would find the equation to the tangent plane at (x,y,z) = (7.5,5,2.5) and that should give the final solution... I'm really not sure if I am correct... I haven't verified my results! Will post if/when I verify my results. Perhaps someone else can let me know if I am right or wrong??
 one year ago

sunsunsun1225Best ResponseYou've already chosen the best response.0
I think you are correct!
 one year ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.