CBSE Class 10 Answered
if nth term of an AP is (2n+1) find the sum of first n terms of AP
Asked by achalgoel | 09 Jan, 2010, 09:13: PM
Expert Answer
an = a + (n-1)d = (2n+1) ...........(1)
Sn = n(2a +(n-1)d)/2
= n(a + (2n+1))/2
where a is the first term, which can be obtained by (1) by using n = 1.
a = 3
Sn = n(3 + (2n+1))/2 = n(n+2)
Regards,
Team,
TopperLearning.
Answered by | 09 Jan, 2010, 11:12: PM
CBSE 10 - Maths
Asked by hanugraha | 30 May, 2010, 07:53: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by hanugraha | 30 May, 2010, 07:13: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by shobhitdc | 29 May, 2010, 04:59: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by ROJAAPPA | 29 May, 2010, 12:58: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by shobhitdc | 29 May, 2010, 10:52: AM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by devanshmudgal | 28 May, 2010, 07:31: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by shobhitdc | 28 May, 2010, 01:12: PM
ANSWERED BY EXPERTCBSE 10 - Maths
Asked by shobhitdc | 28 May, 2010, 01:08: PM
ANSWERED BY EXPERT
