已知多项式(2mx²-x²=3x+1)-(5x²-4y²+3x)
第一题看不懂,请补充完整.
若多项式5x²-2mxy-3y²+4xy-3x+1中不含xy项,
-2m+4=0
m=2
(-m³+2m²-m+1)-(m³+2m²-m+4)的值
=-m³+2m²-m+1-m³-2m²+m-4
=-2m³-3
=-2*2³-3
=-16-3
=-19
已知多项式(2mx²-x²=3x+1)-(5x²-4y²+3x)
第一题看不懂,请补充完整.
若多项式5x²-2mxy-3y²+4xy-3x+1中不含xy项,
-2m+4=0
m=2
(-m³+2m²-m+1)-(m³+2m²-m+4)的值
=-m³+2m²-m+1-m³-2m²+m-4
=-2m³-3
=-2*2³-3
=-16-3
=-19