Q15 of 89 Page 45

If the first term of an AP is - 5 and the common difference is 2, then the sum of the first 6 terms is

Given,


First term, a = - 5


Common Difference, d = 2


Using the formula,



Where Sn is the sum of first n terms


n = no of terms


a = first term


d = common difference


S4 = (6/2)[ 2 (- 5) + (6 - 1)2]


= 3 (- 10 + 10)


= 0

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