Question

Factorise completely 16x^4-81y^4

Answer 1

Hey there,

16x⁴-81y⁴

=(4x²)²-(9y²)²

Since a²-b²=(a+b)(a-b)

=(4x²+9y²)(4x²-9y²)

=(4x²+9y²)[(2x)²-(3y)²]

=(4x²+9y²)(2x+3y)(2x-3y)

HOPE IT HELPS!!!

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07161020
✯ Brainly star ✯
Ace

Answer 2

Hi ,

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We know the algebraic identity ,

a² - b² = ( a + b ) ( a - b )

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16x⁴ - 81y⁴

= 2⁴x⁴ - 3⁴y⁴

= [ (2x)² ]² - [ ( 3y )² ]²

= [ ( 2x )² + ( 3y )² ] [ ( 2x)² - ( 3y )² ]

= ( 4x² + 9y² ) ( 2x + 3y ) ( 2x - 3y )

I hope this helps you.

:)