习题1-2(P31)
巩固
1.(1)11.(2)-11.(3)0.(4)-2.5(5)2.(6)-11.(7)-130.(8)0.2.(1)7.6.(2)-1.(3)--(4)-3(5)-25.(6)-2.5.(7)--(8)二3.(1)-3.(2)0.(3)-0.7.(4)--(5)-10.4.(1)-5.(2)-21二.(3)0.5.(1)23.(2)-30.(3)6.(4)-3
(5)_2(6)-8.3.(7)16.93.(8)-46.37510972(2)-20.75.6.(1)-7.(1)-4.72.(2)-5.96.(3)5.35.8(1)原式=2+1