Find the Differential operator L such that L[x(t)]=0

1) http://www.numberempire.com/equation...Bdt%7D%28xt%29

Ans: http://www.numberempire.com/equation...D%7Bdt%7D%20-t

2) http://www.numberempire.com/equation...8t%5E2x%29]=xt

Ans: http://www.numberempire.com/equation...d%7D%7Bdt%7D-t

Many thanks.