11a(11a+11)-(11a-11)(11+11a)=(11a+11)(11a-(11a-11))=(11a+11)(11a-11a+11)=(11a+11)×11=121a+121→121×4,6+121=121(4,6+1)=121×5,6=677,6
11a(11a+11)-(11a-11)(11+11a)=(11a+11)(11a-(11a-11))=(11a+11)(11a-11a+11)=(11a+11)×11=121a+121→121×4,6+121=121(4,6+1)=121×5,6=677,6