Question

Write the following in sigma notation; n=1. 6+9+27/2+81/4+...

Answer 1

The sigma notation for the series is given below.

$\sum ^{\infty}_{n\mathop=1}=(3^{n\text{ }}.2^{-(\text{ n - 2 )}}\text{ )}$

The above formula is the sigma notation required

If you input each term into the notation above you will get the values of each term.

For example the first term which is 6 was gotten by

$\begin{gathered} \sum ^{\infty}_{n\mathop=\text{ 1}}=(3^1x2^{-(1-2\text{ ) }}) \\ =(3x2^{-(-1\text{ )}}\text{ )} \\ =(3.2^1) \\ =\text{ ( 6 ) ( pls. note that dot above is multiplication sign )} \end{gathered}$

The sigma is therefore the formular above