化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/23 07:25:38
化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3化简求值4x^2-8xy+4y^2/2x^2-2y^2其

化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3
化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3

化简求值4x^2-8xy+4y^2/2x^2-2y^2其中x=2.y=3
4x^2-8xy+4y^2/2x^2-2y^2
=(2x-2y)^2/[2(x^2-y^2)]
=4(x-y)^2/[2(x-y)(x+y)]
=2(x-y)/(x+y)
=-2/5