【x-3/x+3+6x/x²-9】÷1/x²-9,其中x=-√2010
=[(x-3)²+6x]/(x²-9)×(x²-9)
=x²-6x+9+6x
=x²-9
=(-√2010)²-9
=2010-9
=2001
∵(x²-9)不管x取正负值,它的值不变.