若x²+3x-1/3=0 则代数式x-3/3x²-6x÷(x+2-5/x-2)的值
(x-3)/(3x²-6x)÷[(x+2)-5/(x-2)]
=(x-3)/3x(x-2)÷[(x²-4-5）/(x-2)]
=[(x-3)/3x(x-2)]÷[(x-3)(x+3)/(x-2)]
=1/3x÷(x+3)
=1/3(x²+3x)
=1/(3×1/3)
=1