(1)12的相反數(shù)是______;
(2)-22的相反數(shù)是______;
(3)0的相反數(shù)是______;
(4)若m+1與m-3互為相反數(shù),則m=______;
(5)-(x-1)=______;
(6)a+b的相反數(shù)為______;
(7)a-b的相反數(shù)為______.
解:根據(jù)相反數(shù)的定義,得(1)12的相反數(shù)是-12;
(2)-22的相反數(shù)是22;
(3)0的相反數(shù)是0;
(4)∵m+1與m-3互為相反數(shù),∴m+1+m-3=0,解得m=1;
(5)-(x-1)表示x-1的相反數(shù),所以-(x-1)=1-x;
(6)a+b的相反數(shù)為-(a+b)=-a-b;
(7)a-b的相反數(shù)為-(a-b)=b-a.
分析:在一個數(shù)前面放上“-”,就是該數(shù)的相反數(shù).
點評:本題考查了相反數(shù)的意義,一個數(shù)的相反數(shù)就是在這個數(shù)前面添上“-”號;
一個正數(shù)的相反數(shù)是負數(shù),一個負數(shù)的相反數(shù)是正數(shù),0的相反數(shù)是0.