∵向量a⊥量b,∴1*(2x+3)+x*(-x)=0.2x+3-x^2=0.x^2-2x-3=0(x-3)(x+1)=0.x-3=0,x=3； x+1=0,x=-1.∴x3,x2=-1.∵向量a∥b,则,1*(-x)-x(2x+3)=0.-x-2x^2-3x=0.-2x^2-4x=0.x(x+2)=0x=0,或 x=-2 1）当x=0时,向量a=(1,0),...