Question 6

Find the sum to *n* terms of the series 3 × 8 + 6 × 11 + 9 × 14 +…

Answer

The given series is 3 × 8 + 6 × 11 + 9 × 14 + …

*a**n *= (*n*th term of 3, 6, 9 …) × (*n*th term of 8, 11, 14, …)

= (3*n*) (3*n* + 5)

= 9*n*^{2} + 15*n*

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Harsha
2019-09-07 21:32:49

I had to got the answer but to clarify I seen the its correct

Ashutosh pandey
2018-09-24 20:10:37

Very nice

Abc
2018-02-14 10:06:35

Not up to it

- NCERT Chapter