NCERT Class 11 Mathematics Solutions: Chapter 9 –Sequences and Series Miscellaneous Exercise 9 Part 13
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Arithmatic Series
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1. If are the sum of first n natural numbers, their squares and their cubes, respectively, show that
Answer:
From the given information,
So,
…………….. eq (1)
Also,
……………. eq (2)
So, from eq (1) and (2)
2. Find the sum of the following series up to terms:
Answer:
The term of the given series is
Here, is an A.P. with first term , last term and number of terms as .