Ответы и объяснения

2013-04-30T16:58:02+04:00
2013-04-30T21:17:37+04:00

(a+b+2)(a+b)-(a-b)^{2}+1=a^{2}+2ab+b^{2}+2a+2b-(a-b)^{2}+1=a^{2}+2ab+b^{2}+2a+2b-(a^{2}-2ab+b^{2})+1=a^{2}+2ab+b^{2}+2a+2b-a^{2}+2ab-b^{2}+1=2ab+b^{2}+2a+2b+2ab-b^{2}+1=4ab+b^{2}+2a+2b-b^{2}+1=4ab+2a+2b+1=(2b+1)(2a+1)