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Any term of an A.P. (except first) is equal to half the sum of terms which are equidistant from it. - Mathematics

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प्रश्न

Any term of an A.P. (except first) is equal to half the sum of terms which are equidistant from it.

विकल्प

  • True

  • False

MCQ
सत्य या असत्य
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उत्तर

This statement is True.

Explanation:

Let us consider an A.P a, a + d, a + 2d, …

∴ a2 + a4 = a + d + a + 3d

= 2a + 4d

= 2a3

⇒ a3 = `(a_2 + a_4)/2`

 `(a_3 + a_5)/2 = (a + 2d + a + 4d)/2`

= `(2a + 6d)/2`

⇒ a + 3d

= a4 

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अध्याय 9: Sequences and Series - Exercise [पृष्ठ १६४]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 9 Sequences and Series
Exercise | Q 32 | पृष्ठ १६४

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