NCERT Class 11 Mathematics Solutions: Chapter 9 –Sequences and Series Miscellaneous Exercise 9 Part 12

Download PDF of This Page (Size: 140K)

Formulae for Arithmetic Series

Formulae for Arithmetic Series

Formulae for Arithmetic Series

1. Find the 20th term of the series terms.

Answer:

The given series is terms

term

So, the term of the series is .

2. Find the sum of the first n terms of the series:

Answer:

The given series is

On subtracting both the equations, we obtain