第二学期期末测试卷一、选择题(每题3分,共30分)1.函数y=的自变量x的取值范围是()A.x≥0且x≠2B.x≥0C.x≠2D.x>22.下列二次根式中,最简二次根式是()A.B.C.D.3.下列运算正确的是()A.+=3B.2×3=6C.÷=2D.3-=34.当b<0时,一次函数y=x+b的图象大致是()INCLUDEPICTURE"D:\\方正转Word\\8R数点训\\JX14.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\JX14.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\JX14.tif"\*MERGEFORMATINET5.若直角三角形两边长为12和5,则第三边长为()A.13B.13或C.13或15D.156.赵老师是一名健步走运动的爱好者,她用手机软件记录了某个月(30天)每天健步走的步数(单位:万步),将记录结果绘制成了如图所示的统计图.在每天健步走的步数这组数据中,众数和中位数分别是()INCLUDEPICTURE"D:\\方正转Word\\8R数点训\\PJ88.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\PJ88.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\PJ88.tif"\*MERGEFORMATINETA.1.2,1.3B.1.4,1.3C.1.4,1.35D.1.3,1.37.为考察两名实习工人的工作情况,质检部将他们工作第一周每天生产合格产品的个数整理成甲、乙两组数据,如下表:甲26778乙23488关于以上数据,说法正确的是()A.甲、乙的众数相同B.甲、乙的中位数相同C.甲的平均数小于乙的平均数D.甲的方差小于乙的方差8.如图,在△ABC中,点D、E、F分别是边AB、AC、BC的中点,要判定四边形DBFE是菱形,下列所添加条件不正确的是()A.AB=ACB.AB=BCC.BE平分∠ABCD.EF=CFINCLUDEPICTURE"D:\\方正转Word\\8R数点训\\OO71.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\OO71.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\OO71.tif"\*MERGEFORMATINETINCLUDEPICTURE"D:\\方正转Word\\8R数点训\\OO62.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\OO62.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\OO62.tif"\*MERGEFORMATINETINCLUDEPICTURE"D:\\方正转Word\\8R数点训\\D192.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\19春初中\\8R数学\\8R数学点训文件\\D192.tif"\*MERGEFORMATINETINCLUDEPICTURE"E:\\1...