Linear algebra Question

Question

turingtest · Answer

post it please

anonymous · Answer

det(A−λI)=0

anonymous · Answer

where A=  1  -2
                3  -4

experimentx · Answer

http://www.wolframalpha.com/input/?i=%7B%7B1%2C-2%7D%2C%7B3%2C-4%7D%7D+-+l%7B%7B1%2C0%7D%2C%7B0%2C1%7D%7D

anonymous · Answer

I have a question for you (Turning Test) its on my page

turingtest · Answer

Eigenvalues?
$$A-\lambda I=$$
                                 1-lambda         -2
                                  3             -4-lambda 
I'm just going to put an x for lambda because it is easier   
so the determinant is
(1-x)(-4-x)-(3)(-2)=-4-5x+x^2+6=x^2-5x+2
solve for x (really lambda)

turingtest · Answer

Sorry I distributed wrong:
(1-x)(-4-x)-(3)(-2)=-4+3x+x^2+6=x^2+3x+2=0
solve for x (really lambda)

turingtest · Answer

|dw:1318268961548:dw|
=(1-x)(-4-x)-(3)(-2)

anonymous · Answer

ohhh,,, yea... i was doing it like that but it looked weird,,,