化简: ( 2 a 2 + 2 a a 2 − 1 − a 2 − a a 2 − 2 a + 1 ) ÷ 2 a a − 1 .
计算(每小题4分,共16分) (1) (2) (3) (4)
(本题12分)计算: (1) (2) (3) (4)
计算下列各题: (1)(-2)+(-8) (2)1+(-2)+|-2-3|-5 (3) (4) (5)﹣3﹣[﹣5+(1﹣2×)÷(﹣2)](6)25×(-18)+(-25)×12+25×(-10 )
计算(每小题4分,共24分) (1) (2) (3) (4) (5) (6)
计算(每题3分,共12分) (1)8+(-)-5-(-0.25) (2) (3) (4)