Question

प्रथम 24 पदों का योग क्या होगा जिसका n वा पद an =3 +2n .

✋✋✋✋✋✋मदद दोस्तों , solve kro ...easy hai....

Answer 1

an=3+2n
1st term =a1 =3+2(1)
=3+2
=5
2nd term =a2 =3+2(2)
=3+4
=7
3rd term =a3 =3+2(3)
=3+6
=9
4th term =a4 =3+2(4)
=3+8
=11
So, the series is 5, 7, 9, 11 ....
Since 7-5=2
9-7=2
11-9=2
So, the difference of the consecutive terms is same.
Therefore, it is an A.P.

Sn = n/2 [2a+ (n-1)d ]
S24 = 24/2 [2×5 + (24-1) 2]
= 12 [10 + 23×2)]
= 12 ×56
= 672
Hence, the sum of 24 terms is 672.
Thanks :) , by the way your Hindi is very cool.

Answer 2

hello brother...

given :-
an = 3+2n

to find :-
sum of first 24 terms.

solution:-

refers to the attachment..

your answer is 672..

thus, the sum of 1st 24 term is 672..



hope this helps!!!