Q2 of 110 Page 53

Find the sum of the first 30 terms of an A.P. whose nth term is 3 + 2n.

In the A.P.


First term = 3 + 2×1 = 5


No. of terms = 30


Last term = 3 + 2×30 = 63


Sum of terms =


⇒ Sum of terms =


⇒ Sum of terms =


⇒ Sum of terms = 1020


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