If a − 1 a = 10 ; Find a 2 − 1 a 2 - Mathematics

If `"a" - 1/"a" = 10`; find `"a"^2 - 1/"a"^2`

Sum

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

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

= `(±2sqrt(26)) (10)`
= ±20`sqrt(26)`.

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Chapter 4: Expansions - Exercise 4.1

Chapter 4 Expansions
Exercise 4.1 | Q 10.2

Simplify: `(a + b + c)^2 - (a - b + c)^2`

Simplify the following expressions:

`(x + y - 2z)^2 - x^2 - y^2 - 3z^2 +4xy`

Find the following product:

(4x − 3y + 2z) (16x² + 9y² + 4z² + 12xy + 6yz − 8zx)

(a − b)³ + (b − c)³ + (c − a)³ =

Find the square of 2a + b.

Evalute : `((2x)/7 - (7y)/4)^2`

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(b – 3) (b – 5)

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Prove that (a + b + c)³ – a³ – b³– c³ = 3(a + b)(b + c)(c + a).