1. Class 10
  2. Solutions of Sample Papers for Class 10 Boards
  3. CBSE Class 10 Sample Paper for 2019 Boards
Check sibling questions

Question 4 - CBSE Class 10 Sample Paper for 2019 Boards - Solutions of Sample Papers for Class 10 Boards

Last updated at Dec. 16, 2024 by Teachoo

Question 4

If n th term of an A.P. is (2n + 1), what is the sum of its first three terms?

Transcript

Question 4 If nth term of an A.P. is (2n + 1), what is the sum of its first three terms? Given an = 2n + 1 We need to find sum of first three terms Finding first three terms a1 = 2(1) + 1 = 2 + 1 = 3 a2 = 2(2) + 1 = 4 + 1 = 5 a3 = 2(3) + 1 = 6 + 1 = 7 1/2 marks for finding a1, a2, a3 So, Sum of first three terms = a1 + a2 + a3 = 3 + 5 + 7 = 15
  1. Class 10
  2. Solutions of Sample Papers for Class 10 Boards

    3. CBSE Class 10 Sample Paper for 2019 Boards

    CBSE Class 10 Sample Paper for 2018 Boards →
CBSE Class 10 Sample Paper for 2018 Boards →
Class 10
Solutions of Sample Papers for Class 10 Boards

About the Author

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo