计算:
(1) (2)(+1—2.75)×24+ (—1)2014
(本题12分)计算: (1) (2)
计算下列各题 (1) (2) (3) (4)
(本小题满分6分)解方程组 .
化简(每小题4分,共8分) (1)(+)() ; (2)