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Find the Number of (I) Diagonals - Mathematics

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प्रश्न

Find the number of (i) diagonals

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उत्तर

A decagon has 10 sides.
(i)  Number of diagonals =\[\frac{n \left( n - 3 \right)}{2} = \frac{10 \left( 10 - 3 \right)}{2} = 35\]

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अध्याय 17: Combinations - Exercise 17.2 [पृष्ठ १६]

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आरडी शर्मा Mathematics [English] Class 11
अध्याय 17 Combinations
Exercise 17.2 | Q 21.1 | पृष्ठ १६

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