若m^2+n^2-n+4m+17/4=0,m=____,n=_____计算:(1)(2x-3y)^2-(3x+y)(3x-y)(2)(x+y)(x^2+y^2)(x-y)(3)(m-n-3)^2

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若m^2+n^2-n+4m+17/4=0,m=____,n=_____计算:(1)(2x-3y)^2-(3x+y)(3x-y)(2)(x+y)(x^2+y^2)(x-y)(3)(m-n-3)^2
若m^2+n^2-n+4m+17/4=0,m=____,n=_____
计算:(1)(2x-3y)^2-(3x+y)(3x-y)
(2)(x+y)(x^2+y^2)(x-y)
(3)(m-n-3)^2

若m^2+n^2-n+4m+17/4=0,m=____,n=_____计算:(1)(2x-3y)^2-(3x+y)(3x-y)(2)(x+y)(x^2+y^2)(x-y)(3)(m-n-3)^2
m²+n²-n+4m+17/4=0
(m+2)²+(n-1/2)²=0
m=-2,n=1/2
(1)=4x²-12xy+9y²-9x²+y²=-5x²-12xy+10y²
(2)=(x²-y²)(x²+y²)=x^4-y^4
(3)=m²+n²+9-2mn-6m+6n

m=2 n=1/2
(1)4x²-12xy+9y²-(9x²-y²)=4x²-12xy+9y²-9x²+y²=-5x²-12xy+10y²
(2)x^4 -y^4
(3)m²+n²+9-2mn+6n-6m

原式化简为(m+2)^2+(n-1/2)^2 =0.则可以看出m=-2 n=1/2