If A2 - 3a - 1 = 0 and a ≠ 0, Find : a 2 − 1 a 2 - Mathematics

If a² - 3a - 1 = 0 and a ≠ 0, find : `"a"^2 - (1)/"a"^2`

Sum

`"a"^2 - (1)/"a"^2`

= `("a" + 1/"a")("a" - 1/"a")`

= `(±sqrt(13)) (3)`
= ±3`sqrt(13)`.

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Chapter 4: Expansions - Exercise 4.1

Chapter 4 Expansions
Exercise 4.1 | Q 16.3

Factorise:

`2x^2 + y^2 + 8z^2 - 2sqrt2xy + 4sqrt2yz - 8xz`

Verify:

x³ – y³ = (x – y) (x² + xy + y²)

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(a - 0.1) (a + 0.1)

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(x − y) (x + y) (x² + y²) (x⁴+ y⁴) is equal to

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