Arithmetic Progression
Question 2 Deleted for CBSE Board 2025 Exams
Question 3 Important Deleted for CBSE Board 2025 Exams
Question 4 Deleted for CBSE Board 2025 Exams
Question 5 Important Deleted for CBSE Board 2025 Exams
Question 6 Deleted for CBSE Board 2025 Exams
Question 7 Important Deleted for CBSE Board 2025 Exams
Question 8 Deleted for CBSE Board 2025 Exams
Question 9 Important Deleted for CBSE Board 2025 Exams
Question 10 Deleted for CBSE Board 2025 Exams
Question 11 Important Deleted for CBSE Board 2025 Exams
Question 12 Deleted for CBSE Board 2025 Exams
Question 13 Deleted for CBSE Board 2025 Exams
Question 14 Important Deleted for CBSE Board 2025 Exams
Question 15 Important Deleted for CBSE Board 2025 Exams
Question 16 Important Deleted for CBSE Board 2025 Exams
Question 17 Deleted for CBSE Board 2025 Exams
Question 18 Important Deleted for CBSE Board 2025 Exams
Arithmetic Progression
Last updated at April 16, 2024 by Teachoo
Ex 9.2 , 1 Find the sum of odd integers from 1 to 2001. Integers from 1 to 2001 are 1, 2, 3, 4, .2001 Odd integers from 1 to 2001 are 1,3,5, 1999,2001 This sequence forms an A.P as difference between the consecutive terms is constant. So, the A.P. is 1,3,5, 1999,2001 Here First term = a = 1 Common difference = d = 3 1 = 2 & last term = l = 2001 First, we will find number of terms, i.e. n We know that an = a + (n 1)d where an = nth term , n = number of terms, a = first term , d = common difference Here, an = last term = l = 2001 , a = 1 , d = 2 2001 = 1 + (n 1)2 2001 = 1 + 2n 2 2001 1 = 2n 2 2001 1 + 2 = 2n 2002 = 2n 2002/2 = n 1001 = n n = 1001 To calculate sum of odd integers, we use the formula Sn = n/2 [a + l] Here, n = 1001 , l = 2001 & a = 1 Sn = 1001/2 [1 + 2001] = 1001/2 2002 = 1001 1001 = 1002001 Hence the sum of odd integers from 1 to 2001 is 1002001