解不等式组: 4 x - 5 > x + 1 3 x - 4 2 < x .
计算: (1)(﹣12)+(+30)﹣(+65)﹣(﹣47); (2)(﹣1)2×7+(﹣2)6+8.
计算:
计算: (1)()-1-3tan60°+; (2)(a+2)(a-2)-(a-1)2.
计算: (1) (2)