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已知x+y=-2,试计算1/2(x+y)+4(x-y)-3(x-y)-3/2(x+y)-x+y的值

题目详情
已知x+y=-2,试计算1/2(x+y)+4(x-y)-3(x-y)-3/2(x+y)-x+y的值
▼优质解答
答案和解析
1/2(x+y)+4(x-y)-3(x-y)-3/2(x+y)-x+y
=(1/2-3/2)(x+y)+4(x-y)-3(x-y)-(x-y)
=-(x+y)+(4-3-1)(x-y)
=-(-2)+0
=2