Factorize 21x^2 - 2x + 1/21

Factorize `21x^2 - 2x + 1/21`

`= (sqrt21x)^2 - 2 xx sqrt21x xx 1/sqrt21 + (1/sqrt21)^2`

Using idnetity `a^2 - 2ab + b^2 = (a - b)^2`

`= (sqrt21x - 1/sqrt21)^2`

`∴ 21x^2 - 2x + 1/21 = (sqrt21x - 1/sqrt21)^2`

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Chapter 5: Factorisation of Algebraic Expressions - Exercise 5.1 [Page 9]

Chapter 5 Factorisation of Algebraic Expressions
Exercise 5.1 | Q 15 | Page 9

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