已知x+y=6,xy=-2,求(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)的值.

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已知x+y=6,xy=-2,求(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)的值.

已知x+y=6,xy=-2,求(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)的值.
已知x+y=6,xy=-2,求(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)的值.

已知x+y=6,xy=-2,求(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)的值.
(x-y)²=(x+y)²-4xy=36+8=44
x-y=±√44=±2√11
于是
(x^4-y^4)除以x^2+y^2/xy乘以(6x+6y)
=(x²+y²)(x²-y²)*xy/(x²+y²)*(6x+6y)
=xy(x²-y²)*(6x+6y)
=xy(x+y)(x-y)*6(x+y)
=6xy(x+y)²(x-y)
=-12*6²*(±2√11)
=-432*(±2√11)
=±864√11

-2乘以根号下11除以3