问题
解答题
3(a-b)2-(2b+a)(-a+2b)
答案
3(a-b)2-(2b+a)(-a+2b)
=3(a2-2ab+b2)-(4b2-a2)
=3a2-6ab+3b2-4b2+a2
=4a2-6ab-b2.
3(a-b)2-(2b+a)(-a+2b)
3(a-b)2-(2b+a)(-a+2b)
=3(a2-2ab+b2)-(4b2-a2)
=3a2-6ab+3b2-4b2+a2
=4a2-6ab-b2.