计算:−2cos30°+(−1)0−()−1.
计算: (1);(2)(-6)×5×; (3)(-4)×7×(-1)×(-0.25);(4)
计算: (1)(2) (3)
计算: (1)(2) (3)(4)
计算: (+1)+(-2)+(+3)+(-4)+…+(+99)+(-100)
计算: