数学先化简再求值!

来源:学生作业帮助网 编辑:六六作业网 时间:2024/05/17 14:12:21
数学先化简再求值!数学先化简再求值!数学先化简再求值!原式=y(x+2y)(x-2y)/(x+2y)²*(4xy+x²-2xy)/(x-2y)=y(x-2y)/(x+2y)*(x&

数学先化简再求值!
数学先化简再求值!

数学先化简再求值!
原式=y(x+2y)(x-2y)/(x+2y)²*(4xy+x²-2xy)/(x-2y)
=y(x-2y)/(x+2y)*(x²+2xy)/(x-2y)
=y(x-2y)/(x+2y)*x(x+2y)/(x-2y)
=xy
=(√2-1)(√2+1)
=2-1
=1