计算 (1)-9+12-3+8 (2)(-1)+(-)+(+)-(+) (3)(-3)÷2÷(-3)×(-0.75) (4)-16-(1-0.5)××[2-(-3)2]
(6分×2)(1)计算: (2)解方程:
(本题共有2小题,每小题6分,共12分) 计算:(1)4-(-4)+(-3);(2).
计算:.
(1)计算:(2)解方程:
计算:2sin60°+cos60°-3tan30°.