早教吧 育儿知识 作业答案 考试题库 百科 知识分享

x^2-xy-2y^2-x-y=?.

题目详情

▼优质解答
答案和解析
x²-xy-2y²-x-y
=(x²-y²)-(xy+y²)-(x+y)
=(x-y)(x+y)-y(x+y)-(x+y)
=(x-y-y-1)(x+y)-(x+y)---------------------------提取公因式(x+y)
=(x-2y-1)(x+y)