If "A"^2+ 1/"A"^2=23, Find : "A" +1/"A" - Mathematics

If `"a"^2+ 1/"a"^2=23`, find : `"a" +1/"a"`

Sum

`("a"+1/"a")^2="a"^2+1/"a"^2+2`

`⇒("a"+1/"a")^2=23+2`

`⇒("a"+1/"a")^2=25`

`⇒"a"+1/"a"=sqrt25`

`⇒"a"+1/"a"=±5`

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Application of Formulae

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Chapter 12: Identities - Exercise 12 (C) [Page 154]

Chapter 12 Identities
Exercise 12 (C) | Q 7 | Page 154

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