If a + 1a = m and a ≠ 0; find in terms of 'm'; the value of a2-1a2. - Mathematics

If a + `1/a` = m and a ≠ 0; find in terms of 'm'; the value of `a^2 - 1/a^2`.

Sum

`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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Chapter 4: Expansions (Including Substitution) - Exercise 4 (D) [Page 64]

Chapter 4 Expansions (Including Substitution)
Exercise 4 (D) | Q 2.2 | Page 64

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