1、本章整合,一,二,三,四,一,二,三,答案,解析,四,一,二,三,四,一,二,三,解 由题意得x-20,2-x0, 所以x=2.因此y=5, 所以x-y=2-5=-3.,四,一,二,三,四,一,二,三,四,跟踪演练GenZongYanLian,A.0 B.1 C.2 D.3,答案,解析,一,二,三,四,四、实数的相关概念及其大小比较 【例4】 如图,数轴上A,B两点分别对应实数a,b,则下列结论正确的是( )A.a+b0 B.ab0 C.a-b0 D.|a|-|b|0 解析由数轴可知b0,|a|-|b|0.故选C. 答案C,一,二,三,四,跟踪演练GenZongYanLian,A.在2和3之间
2、 B.在3和4之间 C.在4和5之间 D.在5和6之间,答案,一,二,三,5.若a,b均为正整数,且 则a+b的最小值是( ) A.3 B.4 C.5 D.6,答案,解析,四,1,2,3,4,5,6,7,8,9,10,11,12,A.4 B.2 C.2 D.-2,答案,1,2,3,4,5,6,7,8,9,10,11,12,2.(2018湖北荆门中考)8的相反数的立方根是( ),答案,1,2,3,4,5,6,7,8,9,10,11,12,答案,1,2,3,4,5,6,7,8,9,10,11,12,4.(2018山东聊城中考)下列实数中的无理数是( ),答案,1,2,3,4,5,6,7,8,9,1
3、0,11,12,5.(2018贵州黔南州中考)下列四个数中,最大的数是( ),答案,1,2,3,4,5,6,7,8,9,10,11,12,6.(2018江苏南京中考)下列无理数中,与4最接近的是( ),答案,1,2,3,4,5,6,7,8,9,10,11,12,7.(2018福建中考)在实数|-3|,-2,0,中,最小的数是( ) A.|-3| B.-2 C.0 D.,答案,1,2,3,4,5,6,7,8,9,10,11,12,A.5和6之间 B.6和7之间 C.7和8之间 D.8和9之间,答案,1,2,3,4,5,6,7,8,9,10,11,12,9.(2018贵州黔南州中考)下列等式正确的是( ),答案,1,2,3,4,5,6,7,8,9,10,11,12,无理数的个数是( ) A.4 B.3 C.2 D.1,答案,1,2,3,4,5,6,7,8,9,10,11,12,11.(2018四川成都中考)实数a,b,c,d在数轴上对应的点的位置如图所示,这四个数中最大的是( )A.a B.b C.c D.d,答案,1,2,3,4,5,6,7,8,9,10,11,12,答案,