Answers

2016-01-11T21:37:05+05:30
See photo given below
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a little error is here
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2nd last step
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1/2 (5n+3n^2-n-1)
1/2 (3n^2+4n-1)
3 4 3
yes there is an alternative way
but
that is complex
could u show how it is done
yes or no
simple
1st term = 4-1/n
common difference = 3-1/n
substitute these values in SUM equation
its getting complex while u proceed
what will be the final answer plz show how to do step wise