已知x=2,y=-3/2时,求(x²+y²)²-(x²-y²)平方的值
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已知x=2,y=-3/2时,求(x²+y²)²-(x²-y²)平方的值已知x=2,y=-3/2时,求(x²+y²)²-(
已知x=2,y=-3/2时,求(x²+y²)²-(x²-y²)平方的值
已知x=2,y=-3/2时,求(x²+y²)²-(x²-y²)平方的值
已知x=2,y=-3/2时,求(x²+y²)²-(x²-y²)平方的值
(x²+y²)²-(x²-y²)²
=(x²+y²+x²-y²)(x²+y²-x²+y²)
=4x²y²
=4(xy)²
=4x(2x-3/2)²
=4x9
=36
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(x²+y²)²-(x²-y²)²(利用平方差公式)
=(x²+y²+x²-y²)(x²+y²-x²+y²)
=2x²2y²
=4(xy)²
xy=-3
4(xy)²
=4×9
=36;
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(x²+y²)²-(x²-y²)²
=(x²+y²+x²-y²)(x²+y²-x²+y²)
=2x²*2y²
=4x²y²
=4*4*9/4=36