Factorise the Following by the Difference of Two Squares: 441 - 81y2

Factorise the following by the difference of two squares:
441 - 81y²

Sum

441 - 81y²= (21)² - (9y)²= (21 - 9y)(21 + 9y)
= 3(7 - 3y)3(7 + 3y)
= 9(7 - 3y)(7 + 3y).

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Method of Factorisation : Difference of Two Squares

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Chapter 4: Factorisation - Exercise 5.3

Chapter 4 Factorisation
Exercise 5.3 | Q 1.03

Factorise : 25(2a - b)² - 81b²

Factorise : 3a⁵ - 108a³

Factorise : 4x² - 12ax - y² - z² - 2yz + 9a²

Factorise:

(a² − 1) (b²− 1) + 4ab

Factorise : `4x^2 + 1/(4x)^2 + 1`

Factorise the following by the difference of two squares:
625 - b²

Factorise the following by the difference of two squares:
8xy² - 18x³

Factorise the following by the difference of two squares:
(x + y)² -1

Factorise the following by the difference of two squares:
(x - 2y)² -z²

Factorise the following:
y⁴ + y² + 1