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Question
The sum of first n natural numbers is given by `1/2n^2 + 1/2n`. Find the sum of first 5 natural numbers.
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Solution
Given, sum of first n natural numbers = `1/2n^2 + 1/2n`
Sum of first 5 natural numbers = `1/2(5)^2 + 1/2(5)` ...[Put n = 5]
= `25/2 + 5/2`
= `30/2`
= 15
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| S. No |
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Terms | |||||||||
| 1st | 2nd | 3rd | 4th | 5th | ... | 10th | ... | 100th | ... | ||
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| 5 | n2 + 1 | 2 | 5 | 10 | 17 | - | - | - | - | 10001 | - |
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