(3+2 13)-3(1- 13)(1+ 13)

(3+2 13)-3(1- 13)(1+ 13)=2/3-(3+1)(1+1/3)=2/3-4(3+1/3)=2/3-(12-1 1/3)= 2/3-10 2/3=-10

(3+2 13)-3(1- 13)(1+ 13)=-10