\(S=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+...+\frac{1}{43}-\frac{1}{46}\)
\(S=1-\frac{1}{46}=\frac{45}{46}\)
S=1-1/4+1/4-1/7+1/7-1/10+...+1/43-1/46 S=1-1/46 S=45/46 ok S<1
\(S=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+...+\frac{1}{43}-\frac{1}{46}\)
\(S=1-\frac{1}{46}=\frac{45}{46}\)
S=1-1/4+1/4-1/7+1/7-1/10+...+1/43-1/46 S=1-1/46 S=45/46 ok S<1
Chung to rang : (9m+9)(9m+2)(9m+3)(9m+4) chia het cho 5 voi moi m thuoc N
Ai tra loi cau hoi nay toi co 10 nick GIUP TOI GIAI TOAN se vao tung nick de an like cho nguoi --do
- Ai tra loi truoc duoc 3 like
-xong nhi duoc 2 like
-Ai tra loi chinh xac duoc 5 like
GIAI THICH luon nhe cac ban
-nhung nguoi con lai toi cho 1like
cho s =3/1*4+3/4*7+3/7*10+......+3/43*46.chung minh rang s <1
cac ban oi giai gium minh bai nay nhe neu ai giai duoc minh cho 1 like luon ok
chung minh rang :
10 mu n cong voi 5 mu 3 chia het cho 9
43 mu 43 tru cho 17 mu 17 chia het cho 10
nhanh nhe minh muon chu nhat la co cau tra loi cang som cang tot nhe
Cho S = 3/1*4+3/4*7+3/7*10+...+3/40*43+3/43+46. Hãy chứng tỏ S < 1
neu co ba o vuong, o thu 1 co 3 so nhu sau: 2, -1, -3. O thu 2 co 3 so: 5, -4, 3, va o cuoi cung cung co 3 so: -5, 6, 9. Vay nguoi ta hoi lam the nao de cho tong cua ba hop duoc bang nhau, nhung cac ban chi duoc di chuyen mot so cua o nay qua o khac thoi nhe, nho day. Ban nao tra loi duoc cho mik ket ban nhe!
Cho S = \(\frac{3}{1.4}+\frac{3}{4.7}+\frac{3}{7\cdot10}+....+\frac{3}{40\cdot43}+\frac{3}{43\cdot46}\) . Hay chung to rang S < 1
3/4*1+3/4*7+3/7*10+........+3/40*43+3/43*46 chứng mính s<1
ChoS= 3/1*4 +3/4*7 +3/7*10 +.......+ 3/40*43 +3/43*46
Chứng tỏ S <1
cho s=3/1*4+3/4*7+...3/40*43+3/43*46