已知关于x的一元二次方程+(2m-1)x+=0有两个实数根和. (1)求实数m的取值范围; (2)当时,求m的值
66. 除非你保持均衡的饮食,否则将会增加体重。 (a balanced diet, put on weight ) ____________________________________________________________________ 67. 如果天气允许的话,
暑期临近,本溪某旅行社准备组织“亲子一家游”活动,去我省沿海城市旅游,报名的人数共有69人,其中成人的人数比儿童人数的2倍少3人. (1)旅
(1)在等差数列中,,求及前项和; (2)在等比数列中,,求.
如图所示,质量为3m的L形均匀直角棒OAB,下端可绕O轴自由转动,右侧靠在光滑的竖直墙壁上,AB边处于水平状态,已知OA边的长度为AB边的2倍,则此时竖
How to Build Healthy Interpersonal Relationship Human beings are social creatures and thrive(茁壮成长) in relationships with others. A healthy part to be a well-rounded, happy individual is e
写出下列反应的文字表达式并写出基本反应类型: (1)磷在氧气中燃烧___________________ ________;( ) (2)高锰酸钾制取氧气_
I have written to him because he phoned me shortly afterwards. A. ought to B. must C. couldn’t D. needn’t