(1)计算: | - 4 | - ( - 2 ) 2 + 9 - ( 1 2 ) 0
(2)解不等式组 3 x - x ⩾ 2 1 + 2 x 3 > x - 1 .
计算:
先化简再求值:,其中a=-2,.
计算: (1)﹣7﹣11﹣9+5; (2)(﹣1)10×2+(﹣2)3÷4.