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Question
If a + `1/a` = m and a ≠ 0; find in terms of 'm'; the value of `a^2 - 1/a^2`.
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Solution
`a^2 - 1/a^2 = ( a + 1/a )(a - 1/a )` ...[Since a2 - b2 = (a + b)(a - b)]
= `m(+- sqrt(m^2 - 4) )`
= `+-msqrt(m^2 - 4)`
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