己知x十y=5,xy=6,求x(x十y)(x一y)一x(x十y)的平方的值.

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己知x十y=5,xy=6,求x(x十y)(x一y)一x(x十y)的平方的值.
己知x十y=5,xy=6,求x(x十y)(x一y)一x(x十y)的平方的值.

己知x十y=5,xy=6,求x(x十y)(x一y)一x(x十y)的平方的值.
x(x十y)(x一y)一x(x十y)²
=x(x十y)[(x一y)一(x十y)]
=x(x十y)*(-2y)
=-2xy(x+y)
=-2*6*5
=-60

求出X=2 Y=3或X=3或Y=2 分别带入算出就可以了