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已知x+y=2000 x-y=0.005 求x^2-y^2-200x+200y的值
人气:258 ℃ 时间:2020-10-02 03:25:14
解答
x^2-y^2-200x+200y
=(x-y)(x+y)-200(x-y)
=(x-y)(x+y-200)
=0.005*(2000-200)
=0.005*1800
=9
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