Evaluate the infinite geometric series: 1 + 2/7 + 4/49 + 8/343 + ...
Well, I see (2/7)0 + (2/7)1 + (2/7)2 + (2/7)3 + . . .
but I don't know what to do after that.
+678 Hello Guest,
Evaluate the infinite geometric series: 1 + 2/7 + 4/49 + 8/343 + ...
\({\color{red}Solution:}\)
\(1 + \frac{2}{7} + \frac {4}{49} + \frac {8}{343} + \mbox { } ...\)
\( \mathcal{ \mbox {Like Guest said it right } } \mbox { } (^2/_7)^0 + (^2/_7)^1 + (^2/_7)^2 + (^2/_7)^3 + \mbox { } ...\)
Use the double summation sign \(\sum\) .
\(\displaystyle\sum_{n=1}^{\infty} \Bigl( \frac {7}{2} \Bigr)^{1 - n} = \frac {7}{5} = 1.4 \) .
\(\mathit{ Straight}\)
