若多项式(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关,求2m^2-(3m^2+4m-5+m)的值?

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若多项式(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关,求2m^2-(3m^2+4m-5+m)的值?
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若多项式(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关,求2m^2-(3m^2+4m-5+m)的值?
若多项式(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关,求2m^2-(3m^2+4m-5+m)的值?

若多项式(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关,求2m^2-(3m^2+4m-5+m)的值?
展开得2mx^2-x^2+3x+1-5x^2+4y^2-3x=(2m-6)x^2+4y^2+1,因为此多项式与x无关,所以2m-6=0,即m=3;
所以2m^2-(3m^2+4m-5+m)=2*9-(3*9+4*3-5+3)=-19

(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)与X无关
=2mx^2-x^2+3x+1-5x^2+4y^2-3x
=(2m-1)x^2+1-5x^2+4y^2
2m-1=5
m=3
2m^2-(3m^2+4m-5+m)
=2m^2-3m^2-4m+5-m
=-m^2-5m+5
=-9-15+5=-19

原式=(2m-6)x^2+4y^2+1
∵原式于x无关
∴2m-6=0 m=3
∴2m^2-(3m^2+4m-5+m)
=-m^2-5m+5
=-9-15+5
=-19

(2mx^2-x^2+3x+1)-(5x^2-4y^2+3x)
=(2m-6)x^2+4y^2+1
与x无关,m=3
所以2m^2-(3m^2+4m-5+m)
=-m^2-5m+5
=-19