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Question
If a ≠ 0 and `a - 1/a` = 3 ; find `a^2 + 1/a^2`
Sum
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Solution
`a - 1/a = 3`
Squaring both sides,
⇒ `(a - 1/a)^2 = 3^2`
⇒ `a^2 + (1/a)^2 - 2(a) (1/a) = 9`
⇒ `a^2 + 1/a^2 - 2 = 9`
⇒ `a^2 + 1/a^2 = 11`
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