问题
解答题
(1)计算:16÷(-2)3+(2009-
(2)先化简,再求值:
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答案
(1)原式=-16÷8+1-(
-1)+3×3 2 3 3
=-2+1-
+1+23 3
=
…(8分)3
(2)原式=
÷x(x-2) (x+1)(x-1) x2-1-2x+1 x+1
=
•x(x-2) (x+1)(x-1) x+1 x(x-2)
=
,1 x-1
当x=
时,原式=-2.…(8分)1 2