化简:(1)(2m-n²)-(-3n²+9m);(2)2x²-4/3(4x-6x²)+(x-3x²).
问题描述:
化简:(1)(2m-n²)-(-3n²+9m);(2)2x²-4/3(4x-6x²)+(x-3x²).
答
(2m-n2)-(-3n2+9m)=2m-n2-3n2-9m=-7m-4
化简:(1)(2m-n²)-(-3n²+9m);(2)2x²-4/3(4x-6x²)+(x-3x²).
(2m-n2)-(-3n2+9m)=2m-n2-3n2-9m=-7m-4