若A=2a²-ab+b²,B=a²-2b²,则2分之1A+3分之1B=

若A=2a²-ab+b²,B=a²-2b²,则2分之1A+3分之1B=
若A=2a²-ab+b²,B=a²-2b²,则2分之1A+3分之1B=

若A=2a²-ab+b²,B=a²-2b²,则2分之1A+3分之1B=
解A/2+B/3
=(3A/6+2B/6)
=(3A+2B)/6
=[2(2a^2-ab+b^2)+2(a^2-2b^2)]/6
=[4a^2-2ab+2b^2+2a^2-4b^2]/6
=[6a^2-2ab-2b^2]/6
=（3a^2-ab-b^2）/3