tim so tu nhien x biet
(2.x+1)mu 5 /(2.n+1)mu 2=1
2 mũ x+2 .2 mu x+........+10.2 mu x =10 . 11
dau / nay la dau chia
dau . nay la nhan do nhe!!!!
2 mu m cong 2 mu n bang 2 mu m cong n tim m va n
so chinh phuong la so bang binh phuong cua mot so tu nhien ( vi du 0 ,1,2,4,9,16,...0) moi tong sau day co so chinh phuong ko
a) 1mu 3 +2 mu 3
b)1mu 3+2mu 3 +3 mu 3
c)1 mu 3+ 2 mu 3 + 3 mu 3 +4 mu 3
tai minh ko biet go dau mu !
tim so tu nhien n,biet: a) (2mu n+1)=27 b) (n-2)mu 2=(n-2)mu 4 c)3 mu n+1=81 d)2mu2n+1=512
a) 2345-1000:[19-2(21-18)mu 2]
b)107-{38+[7.3 mu 2-24:6+(9-7) mu 3]} :15
c) 10- [(2 mu 2-48).5+(2 mu 3 .10+8)]:28
2) tim so tu nhien a,biet rang a gan den 1000,a:12,a:21 deu co du la 5
3) tim boi chung lon hon 5000 be hon 10000 cua cac so 126;140;180.
n>2.CMR NEU N CHIA HET CHO 3 THI N MU 2 TRU 1 VA N MU 2 CONG 1 KO DONG THOI CUNG LA SO NGUYEN TO
tim n biet :
a) 2 mu n = 2 b) am 3 mu n chia 8 mu 1 c) 8 mu n chia 2 mu n =4
tim so tu nhien abc nhat thoa man
abc= n mu 2 -1 va cba= n mu 2 -4n +4
viet tong sau thanh binh phuong cua mot so tu nhien , n lon hon hoac bang 1
1 mu 8 + 2 mu 8 + 3 mu 8 ......... n mu 8
