(a+1)^2-2(a+1)(a-1)+3(a-1)^2(a+1)^2-2(a+1)(a-1)+3(a-1)^2(过程要带啊),老师叫我讲,正确的

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(a+1)^2-2(a+1)(a-1)+3(a-1)^2(a+1)^2-2(a+1)(a-1)+3(a-1)^2(过程要带啊),老师叫我讲,正确的

(a+1)^2-2(a+1)(a-1)+3(a-1)^2(a+1)^2-2(a+1)(a-1)+3(a-1)^2(过程要带啊),老师叫我讲,正确的
(a+1)^2-2(a+1)(a-1)+3(a-1)^2
(a+1)^2-2(a+1)(a-1)+3(a-1)^2(过程要带啊),老师叫我讲,正确的

(a+1)^2-2(a+1)(a-1)+3(a-1)^2(a+1)^2-2(a+1)(a-1)+3(a-1)^2(过程要带啊),老师叫我讲,正确的
直接解(a+1)^2-2(a+1)(a-1)+3(a-1)^2
=a^2+2a+1-2a^2+2+3a^2-6a+3
=2a^2-4a+6
较简便的(a+1)^2-2(a+1)(a-1)+3(a-1)^2
=[(a+1)-(a-1)]^2+2(a-1)^2
=4+2a^2-4a+2
=2a^2-4a+6
我本助人为乐而解,这里省了几步,我一般都会这样写,不知你能看懂吗

2a^2-4a+6

设a+1为A a-1为B 原式为 A^2-2AB+3B^2=(A+B)^2+2B^2=4a^2+2(a-1)^2=8a^2-4a+2

原式=2a+2-2(a的平方-1)+(3a-3)*2
手机回答,条件有限、采纳哦~
=8a-2*a的平方-6

2a^2+3