Math, asked by aisaankhan, 1 year ago

if the sum of n terms of an ap be 3n²+n and its common difference is 6 then its first term is​


darkcrafter09: Just put 1 in place of n
darkcrafter09: The answer is 4
aisaankhan: 3n²_n=n/2(2a+(n_1). 3(1)²_1=1/2(2a+(1_1)6. 3_1=1/2 2a. a=2

Answers

Answered by ddkannan123
14

Answer:

Step-by-step explanation:

Attachments:
Answered by Aqua08
12

Sn = 3n² + n

d = 6

If n = 1,

S1 = 3×1²+1

    = 4

S1  = a = 4

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