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what is the sum of 4+18+48+100+180+294+448+....up to 28 terms?
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- 180670
the series is n[(n+1)^2]...apply the summation formula till n=28
(n^2)[(n+1)^2]/4 + n(n+1)/2 + 2n(n+1)(2n+1)/6
put n=28 to get ans= 180670 - 10 years agoHelpfull: Yes(10) No(7)
- "180670"
the series is " n[(n+1)^2] " in this pattern
Case 1 put n=1
u will get "4"
Case 2 put n="2"
u will get "18
Case 3 put n="3"
u will get "48"
and so on
put n=28 to get ans= 180670 - 10 years agoHelpfull: Yes(4) No(3)
- Dear pal,I could not get the calculation.Could you explain it plz?
- 10 years agoHelpfull: Yes(3) No(1)
- What is the summation formula??@ABHYUDAY PAL
- 10 years agoHelpfull: Yes(3) No(2)
- 180670
the series is n[(n+1)^2]...apply the summation formula till n=28
(n^2)[(n+1)^2]/4 + n(n+1)/2 + 2n(n+1)(2n+1)/6
put n=28 to get ans= 180670 - 10 years agoHelpfull: Yes(2) No(1)
- series can be written as n[(n+1)^2]
then re-arrange as :-
(2-1)*2^2+(3-1)*3^2+...........+(29-1)29^2
(1^3+2^3+3^3+............+29^3) - (1^2+2^2+3^2+........+29^2) = 180670 - 9 years agoHelpfull: Yes(2) No(0)
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