Example 1 - Chapter 9 Class 11 Sequences and Series (Term 1)
Last updated at Oct. 5, 2021 by Teachoo
Chapter 9 Class 11 Sequences and Series (Term 1)
Concept wise
-
Finding Sequences
- Arithmetic Progression (AP): Formulae based
- Arithmetic Progression (AP): Statement
- Arithmetic Progression (AP): Calculation based/Proofs
- Inserting AP between two numbers
- Arithmetic Mean (AM)
- Geometric Progression(GP): Formulae based
- Geometric Progression(GP): Statement
- Geometric Progression(GP): Calculation based/Proofs
- Inserting GP between two numbers
- Geometric Mean (GM)
- AM and GM (Arithmetic Mean And Geometric mean)
- AP and GP mix questions
- Finding sum from series
- Finding sum from nth number
Transcript
Example 1 Write the first three terms in each of the following sequences defined by the following: an = 2n + 5 We need to find first three terms i.e. a1, a2, a3 Given an = 2n + 5 putting n = 1 in (1) a1 = 2(1) + 5 = 2 + 5 = 7 Putting n = 2 in (1) a2 = 2(2) + 5 = 4 + 5 Putting n = 3 in (1) a3 = 2(3) + 5 = 6 + 5 = 11 Hence first three terms are 7, 9 and 11.
