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sum of 44,42,40,...?
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- The series is as 44,42,40, ....(Its a infinite Series)
The max value can be obtained when the series will have +ve elements in it.
So the max sum will be (44+ 42+ ....+ 2) which is an AP with common Difference -2.
So the sum = n(1st + Last term)/2. Here can be obtain by the formula Tn = a + (n-1)*d. Which will give n = 22. By putting Tn = 2,a = 44 & d = -2
So Sum = 22(44+2)/2 = 506. - 11 years agoHelpfull: Yes(12) No(0)
- SUM IS MAX WHEN LAST TERM = 0
=>COMMON DIFFERENCE=-2
SUM=N/2(FIRST+LAST)
23/2(44+0)
=>506
- 11 years agoHelpfull: Yes(9) No(0)
- The sum is maximum if the series does not goes to (-ve)
hence the given series is 44,,42,40........0
Let no. of terms in this series is n
0=44+(n-1)(-2)
hence n=23
now the sum of these 23 terms of series is
23/2[2*44+22*(-2)]
23/2*44
23*22
=506
- 11 years agoHelpfull: Yes(8) No(0)
- 44,42,40,…
This is a decreasing AP. If you leave it like that, it will go in to negative terms -2,-4,….
But to make the sum maximum, we need to stop at ‘0’. Otherwise the –ve terms make the sum decrease.
So the series is 44,42,40,…..0.
44+42+40+…+0 = 2(22+21+20+…0) = 2(sum of first 22 integers) = 2(n*(n+1)/2), where n =22
=> Sum = 2*(22*23/2) = 22*23 = 506
Ans:506 - 10 years agoHelpfull: Yes(1) No(0)
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