Question

因式分解分组法x方+y方-a方-b方+2xy+2ab分组法

Answer 1

x^2+y^2-a^2-b^2+2xy+2ab

=(x^2+2xy+y^2)-(a^2-2ab+b^2)

=(x+y)^2-(a-b)^2

=(x+y-a-+b)(x+y+a-b)