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1(1!)+2(2!)+3(3!)....2012(2012!) what is the sum of the series?
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- 1(1!)+2(2!)=5 => 3!-1
1(1!)+2(2!)+3(3!)=23 => 4!-1
1(1!)+2(2!)+3(3!)+.............+2012(2012!)=2013!-1 - 10 years agoHelpfull: Yes(70) No(0)
- 1!=2!-1
1(1!)+2(2!)=3!-1
1(1!)+2(2!)+3(3!)=4!-1
simalarly 2012(2012!) Is 2013!-1 - 10 years agoHelpfull: Yes(26) No(0)
- 1(1!)+2(2!)+3(3!)....2012(2012!)=summation of n.n!
n.n!=(n+1-1)n!=(n+1)n!-n!=(n+1)!-n!
by putting values of n=1,2,..................2012
we get 2013!-1 - 10 years agoHelpfull: Yes(3) No(1)
- ans is 2013!-1
1(1!)+2(2!)..........+2012(2012!)=2013!-1 - 10 years agoHelpfull: Yes(2) No(0)
- 1(1!)+2(2!)+3(3!)....2012(2012!)
when this type of prob given... just take a look at its maximum range...
so it will be [(n+1)!-1]
Hence it will be as (2012+1)!-1=(2013)!-1
BUT IF IT IS LIKE 1!+2!+3!....(2012!)
THEN, it will be (n+1)!=2013! - 10 years agoHelpfull: Yes(2) No(2)
- if the given question is 1(1!)+2(2!)+3(3!)....2012(2012!)
then answer is 2013!-1
1(1!)+2(2!)+3(3!).................n(n!)=(n+1)!-1
- 10 years agoHelpfull: Yes(0) No(0)
- 2012!=2012*2011*2010........*1
now for 2012(2012!)=2012*2012*2011*...*1
=(2013*2012*2011*...*1)-1
=2013!-1 - 10 years agoHelpfull: Yes(0) No(0)
- simple approach to solve this question is to take first 3 number that is mention in equation
i.e 1(1!)+2(21)+3(3!)
now cal calculate this 1(1!)+2(21)+3(3!) will come 23 which is 4!-1 so take a 1 more a highest factorial mention and subtract 1 in this case 2013!-1 - 10 years agoHelpfull: Yes(0) No(1)
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