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sagar12345
Oct 29, 2009, 07:01 AM
Let A be a 3*3 matrix with eigenvalues 1,-1 and 3.then

sagar12345
Oct 29, 2009, 07:05 AM
Find the critical points of the function f(x,y)=x^3+y^2-12x-6y+40 test each of these for maximum and minimum

galactus
Oct 29, 2009, 08:20 AM
Let A be a 3*3 matrix with eigenvalues 1,-1 and 3.then

Then? What are you supposed to do?

Find the characteristic polynomial? I don't know.

A 3 by 3 matrix will have a cubic as a charpoly.

({\lambda}+1)({\lambda}-1)({\lambda}-3)={\lambda}^{3}-3{\lambda}^{2}-{\lambda}+3

Do you have to find the eigenvectors? Let us know what you need to do. We are good, but not mindreaders.:D

galactus
Oct 29, 2009, 08:21 AM
Find the critical points of the function f(x,y)=x^3+y^2-12x-6y+40 test each of these for maximum and minimum

Assistance given in other post regarding same problem.