roitrt区块链
发布时间: 2022-04-06 15:44:19
1. 已知x加y等于1,xy等于负2分之一,求x(x加y)(x减y)减x(x加y)的平方的值
x+y=1,xy= -1/2
x(x+y)(x-y)-x(x+y)^2
=x(x+y)(x-y-x-y)
= -2xy(x+y)
=-2*(-1/2)*1=1
热点内容
1. 已知x加y等于1,xy等于负2分之一,求x(x加y)(x减y)减x(x加y)的平方的值
x+y=1,xy= -1/2
x(x+y)(x-y)-x(x+y)^2
=x(x+y)(x-y-x-y)
= -2xy(x+y)
=-2*(-1/2)*1=1