Find 2 linearly independent eigenvectors and a eigenvalue

[bodensee9]

Hi

I am supposed to, without calculation, find 2 linearly independent eigenvectors and a eigenvalue of the following matrix A

5 5 5
5 5 5
5 5 5

The eigenvalue is easy -- it is 15. And I can find one eigenvector, [1 1 1] (written vertically), but another without calculation? Is there a trick that I should see? Of course, zero is also a eigenvalue, but how am I supposed to find the other eigenvector without calculation? Is there something that I should see?

Thanks.

 

[Dick]

Pick the vector (x,y,z) so that 5x+5y+5z=0. Say, (1,1,-2)?

 

[bodensee9]

oh thanks!