Tính
\(A=\frac{1}{2}+\frac{1}{2^2}+...+\frac{1}{2^9}\)
\(B=\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+\frac{1}{108}+\frac{1}{324}+\frac{1}{972}\)
Tính B=\(\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+\frac{1}{108}+\frac{1}{324}+\frac{1}{972}+\frac{1}{2916}+\frac{1}{8748}\)
Tính \(\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+\frac{1}{108}+\frac{1}{324}+\frac{1}{972}\)
a) \(A=\frac{1}{2}+\frac{1}{2^2}+...+\frac{1}{2^9}\)
b)\(B=\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+\frac{1}{108}+\frac{1}{324}+\frac{1}{972}\)
Tim a,b biet\(a+b=3\left(a-b\right)=2\frac{a}{b}\)
A=\(\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+\frac{1}{108}+\frac{1}{324}+\frac{1}{972}\)
B=\(\frac{1}{1.4}\)+ \(\frac{1}{12}\)+\(\frac{1}{36}\)+\(\frac{1}{108}\)+\(\frac{1}{324}\)+\(\frac{1}{972}\)
ai nhanh tick
Tính
B\(\frac{1}{4}+\frac{1}{12}+\frac{1}{36}+.....+\frac{1}{972}\)
cho \(A=\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{107}+\frac{1}{108}\);\(B=\frac{108}{1}+\frac{107}{2}+\frac{106}{3}+...+\frac{2}{107}+\frac{1}{108}\).tính\(\frac{A}{B}\)
\(A=\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{108}+\frac{1}{109}\) và \(B=\frac{108}{1}+\frac{107}{2}+...+\frac{2}{107}+\frac{1}{108}\).Tính \(\frac{A}{B}\)