【单选题】Dave was newly hired by our company,and he is a good choice for the position since he gained rich experience when he was working for another company .
【简答题】Dave was newly hired by our company,and he is a good choice for the position since he gained rich experience when he was working for another company.
【简答题】已知f(x)是定义在实数集R上的不恒为0的函数,对任意实数x,y有f(x)f(y)=f(x+y),当x>0时,有0<f(x)<1. (Ⅰ)求f(0)的值,并证明f(x)恒正; (Ⅱ)判断f(x)在实数集R上单调性; (Ⅲ)设S n 为数列{a n }的前n项和,a 1 = 1 3 ,a n =f(n)(n为).令b n =f(S n ),问数列{b n }中是否存在最大项?若存在,求出最大项...
【简答题】下列四个命题中: ①设经x,y∈R,则“x≥2且y≥2”是“x 2 +y 2 ≥4”的必要不充分条件; ②命题“所有能被2整除的整数都是偶数”的否定是:“存在一个能被2整除的整数不是偶数”; ③已知命题“如果|a|≤1,那么关于x的不等式(a 2 -4)x 2 +(a+2)x-1≥0的解集为?”,它的逆命题是假命题; ④“m=1”是“直线(m+2)x+my+1=0与直线(m-2)x+(m+2)y-...
【简答题】写给自己一份信,并附上自己最喜欢的图片。
【单选题】稀缺性是指
C.
相对于人类的无限欲望而言,资源与经济物品是不足的
【单选题】设 I 是整数集合, R 是同余模 5 的关系,即 R={ |x ∈ I,y ∈ I ∧ x≡y(mod 5)} ,确定由 I 的元素所产生的等价类中正确的是
【简答题】根据药物对增殖周期中各期肿瘤细胞作用不同,抗癌药可分为哪几类?