【单选题】What’s the disadvantage of e-mail according to the passage?
A.
It has to many junk mails.
B.
I t has no way to know if the person has read the message immediately .
C.
It assumes that the minute someone receives an e-mail, the person will read it.
【单选题】What’s the theme(主题)of E.T?
【简答题】已知数列{ a n }满足 a 1 =0, a 2 =2,且对任意 m 、 n ∈ N * 都有 a 2 m - 1 + a 2 n - 1 =2 a m + n - 1 +2( m - n ) 2 (Ⅰ)求 a 3 , a 5 ; (Ⅱ)设 b n = a 2 n + 1 - a 2 n - 1 ( n ∈ N * ),证明:{ b n }是等差数列; (Ⅲ)设 c n =( a n+1 - a...
【单选题】电压比较器电路如图a所示,则当输入电压uI的波形如图b所示时,灯泡HL的亮暗状态为( )【图片】
【简答题】已知数列{ }满足a 1 =0,a 2 =2,且对任意m、n∈N*都有a 2m﹣1 +a 2n﹣1 =2a m+n﹣1 +2(m﹣n) 2 (1)求a 3 ,a 5 ; (2)设b n =a 2n+1 ﹣a 2n﹣1 (n∈N*),证明:{b n }是等差数列; (3)设c n =( +1 ﹣ )q n﹣1 (q≠0,n∈N*),求数列{c n }的前n项和S n .
【单选题】What’s the trends showed inP4?
A.
Young people are changing in agenda.
B.
Young people cannot live without their parents.
C.
Young people needs friends.
D.
Young people are likely t shift to a new career.
【判断题】设有两个正规格化数:N 1 =2 m ×M 1 , N 2 =2 n ×M 2 ,若m>n,不一定 N 1 > N 2 。