已知A=-3x^2-2mx+3x+1,B=2x^2+mx-1,且2A+B的值与x无关,求m的值.

已知A=-3x^2-2mx+3x+1,B=2x^2+mx-1,且2A+B的值与x无关,求m的值.
9a^3-[-6a^2+2(-a^3-三分之二a^2)] a=-2
求求求求求

2A+B=2(-3x^2-2mx+3x+1)+2x^2+mx-1
= -6x^2-4mx+6x-2+2x^2+mx-1
= -4x^2-3mx-6x-3
= -4x^2-3(m-2)x-3 ----------- 与x无关是不可能的
9a^3-[-6a^2+2(-a^3-三分之二a^2)]
=9a^3-(-6a^2-2a^3-4a^2/3)
=9a^3+6a^2+2a^3+4a^2/3
=11a^3+(22/3)a^2
=11a^2(a+2/3)
=11x(-2)(-2+2/3)
= -22x(-4/3)
= 88/3