Summation Notation

Question

1+3+9+27+81+243

 

Write the sum with the Sigma Notation

Answer 1

We look for a pattern among the numbers.  Notice the numbers are multiples of 3 and that the succeeding terms of the sum are exponential.

 

     5

     ∑  (3ⁿ)

  n = 0

 

 

0 is the initial evaluator of the terms in the sum.  5 is the final evaluator of the terms in the sum.

 

 

(3⁰) + (3¹) + (3²) + (3³) + (3⁴) + (3⁵)=

 

  1   +  3    +  9   +   27  +  81  +  243

Answer 2

∑(3 to the 'x' power)

x=0-5

 

Good luck!