=[2la puterea(12+18)+5la puterea (2·65)/5la puterea 10-3la puterea (5·2·2)]/[2laputerea(2·2+3+23)+5la puterea (15·2·3)-3la puterea (2·5·2)]=
=[2la puterea 30+5la puterea 130/5la puterea 10-3la puterea 20]/[2la puterea30+
5la puterea 90-3la puterea 20]=
=[2la puterea 30+5la puterea (130-20)-3la puterea 20]:[2la puterea 30+5la puterea 90-3la puterea 20]=
=2la puterea(30-30)+5la puterea (110-90)-3la puterea (20-20)=2 la puterea 0+5la puterea 20-3la puterea zero=1+5la puterea 20-1=5 la puterea 20