Help me with this Algebra Question

1. Sep 16, 2009

helib

Can you please provide an example of 2x2 matrices A and B, where exp(A+B)$$\neq$$exp(A).exp(B)

2. Sep 16, 2009

Dick

If A and B commute (i.e. AB=BA), then exp(A+B)=exp(A)exp(B). Can you find an example of two 2x2 matrices that don't commute?