B的a应该是x吧,b应该是y吧
A=2X^2+3xy-2x-1,B=4xy-2y^2-x^2
3A+6B=(6-6)x^2+(9+24)xy-6x-12y^2-3=33xy-6x-12y^2-3=(33y-6)x-12y^2-3
所求值与x无关,则有33y-6=0,y=2/11
B的a应该是x吧,b应该是y吧
A=2X^2+3xy-2x-1,B=4xy-2y^2-x^2
3A+6B=(6-6)x^2+(9+24)xy-6x-12y^2-3=33xy-6x-12y^2-3=(33y-6)x-12y^2-3
所求值与x无关,则有33y-6=0,y=2/11