Question

Factorise : x⁴ - y⁴

Answer 1

$<b><font face=Copper black size=4 colour=purple>$
$<b><marquee direction = "up" > <h3>$Given⁴ - y⁴

= ( x² )² - ( y² )²

{ Using identity

a² - b² = ( a + b ) ( a - b ) }

= ( x² + y² ) ( x² - y² )

Again using the identity

= ( x² + y² ) [ ( x )² - ( y )² ]

= ( x² + y² ) ( x + y ) ( x - y )

^^"

Answer 2

Factorisation :

x⁴-y⁴

= (x²)² - (y²)²

Now putting the identity : A²-B² = (A+B)(A-B)

(x²+y²)(x²-y²)

Again putting the above identity here :

(x²+y²) (x+y)(x-y)

Thank you


Extra identity :

(A²+B²) = (A+B)(A+B)-2AB

(x+y)(x+y)-2xy (x+y)(x-y)