Please solve 22

\fExample 3 If 0 3 4 A = 0 0 6 0 0 0 then 0 0 18 0 0 A2 0 0 0 and A 3 = 0 0 0 0 0 0 so A" = 0 for n 2 3. It therefore follows from Eq. (24) that eAt =I+At+ JA2+2 0 18 0 +2; 0 that is, 1 3t 4t + 9t2 eat = 0 1 6t 0 0 1In Problems 21 through 24, show that the matrix A is nilpotent and then use this fact to find (as in Example 3) the matrix exponential eat. 21. A = 4 22. A = -6