\(S=1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+.....+\frac{1}{2187}\)
A) P=18x31+78x24+78x17+22x72
B) S=\(1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+...........\frac{1}{2187}\)
\(\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+..........\frac{1}{2187}\)
\(1+\frac{1}{3}=\frac{1}{9}+\frac{1}{27}+...+\frac{1}{2187}\)
Tính nhanh \(\frac{1}{1}+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+\frac{1}{243}+\frac{1}{729}+\frac{1}{2187}\)
Tính nhanh: \(B=\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+...+\frac{1}{2187}\)
\(\frac{1}{3}\)+\(\frac{1}{9}\)+\(\frac{1}{27}\)+\(\frac{1}{61}\)+.......+\(\frac{1}{2187}\)=
Tính nhanh :
\(\frac{1}{3}\)+\(\frac{1}{9}\)+ \(\frac{1}{27}\)+ \(\frac{1}{81}\)+ \(\frac{1}{243}\)+ \(\frac{1}{729}\)+ \(\frac{1}{2187}\)
Giúp mình nha !
Bài 18 Tính
\(\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+\frac{1}{243}+\frac{1}{729}+\frac{1}{2187}\)
Bài 15 : Trong các phân số : \(\frac{2004}{2005};\frac{2005}{2006};\frac{2006}{2007};\frac{2007}{2008}\)phân số nào nhỏ nhất
Bài 22: so sánh các phân số
\(\frac{111111}{151515}\)và \(\frac{11022}{15030}\)