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Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 12 - Mathematics and Statistics

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प्रश्न

Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 12

योग

उत्तर

In an n-sided polygon, there are ‘n’ points and ‘n’ sides.

∴ Through ‘n’ points we can draw nC2 lines including sides.

∴ Number of diagonals in n sided polygon

= nC2 – n   ...(n = number of sides)

n = 12, nC2 – n  = 12C2 – 12

= `(12 xx 11)/(1 xx 2) - 12`

= 66 – 12

= 54

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Properties of Combinations
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Permutations and Combination - Exercise 3.6 [पृष्ठ ६५]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] 11 Standard Maharashtra State Board
अध्याय 3 Permutations and Combination
Exercise 3.6 | Q 11. (c) | पृष्ठ ६५

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