Các câu hỏi tương tự
cho A = 1+2+3+4+...+n va B = 2n + 1 ( voi n thuoc N , n lon hon hoac bang 2) chung minh A va B la hai so nguyen to cung nhau
hay viet cac tap hop sau bang cach khac
A={ 9;11;13;...;99]
B={ 12 ; 24 ; 36 ;48}
M= { THANG 4 ; THANG 6 ;THANG 9 ; THANG 11}
N = { X THUOC N / X LON HON HOAC BANG 3 , LON HON HOAC BANG 10}
Q = { X THUOC N / X LON HON 0 ,BE HON 10}
Tap hop A x thuoc N 2 lon hon hoac bang va be hon hoac bang 78.
(1+1/2)×(1+1/3)×(1+1/4)×....×(1+1/n)
Tim n biet n thuoc N va n lon hon hoac bang 2
Cho day so sau : 1, 2, 3, ..., 200 ( 200 so ). Chon n so ( n lon hon hoac bang 2 ) sao cho co 2 so bat ki trong n so do sao cho tong cua 2 trong n so bat ki do chia het cho 2 voi n lon nhat.
So lien truoc cua so 3m -1 la so nao?( Voi m thuoc N va m lon hon hoac bang 2)
1. cho 4 stn a lon hon hoac bang b, b lon hon hoac bang c, clon hon hoac bang d.
CM:(a-b)(a-c)(a-d)(b-c)(b-d)(c-d)
2. CM: co the tim dc 1 stn k sao cho: (1997^k)-1 chia het cho 10^4
3. tong cac chu so cua 1 so chinh phuong co the bang 1995 dc k?
4. tong cua 1995 stn khac 0 dung bang 1995. Hoi UCLN cua chung la bao nhieu?
So lien truoc cua 4.z -1 la so nao? (Voi z thuoc N va z lon hon hoac bang 2)
Xem chi tiết
A={x thuoc N /7nho hon hoac bang x nho hon hoac bang 50, x chia het cho 7
a, viet tap hop A bang cach liet ke cac phan tu
b, tim sophan tu cua tap hop tren