Question 5

Find the sum to *n* terms of the series 5^{2} + 6^{2} + 7^{2} + ... + 20^{2}

Answer

The given series is 5^{2} + 6^{2} + 7^{2} + … + 20^{2}

*n*th term, *a*_{n} = ( *n* + 4)^{2} = *n*^{2} + 8*n* + 16

16th term is (16 + 4)^{2} = (20)^{2}

^{}

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Vashesh Jogani
2019-07-05 17:06:42

From 5 to 16 there are 16 terms so 16

Meghraj
2019-03-23 19:01:20

Why 16?????

Aastha sharma
2018-12-13 15:49:45

How 16cant understand?

Deep
2018-11-30 17:59:41

Good

Guru
2018-11-10 10:15:16

How 16 I don't understand

- NCERT Chapter