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Question
The sum of first n natural numbers is given by the expression `n^2/2 + n/2`. Factorise this expression.
Solution
We have, the sum of first n natural numbers = `n^2/2 + n/2`
Factorisation of given expression = `1/2(n^2 + n) = 1/2n(n + 1)` ...[Taking n as common]
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