Find the product:

(2x – 3y)(2x + 3y)(4x² + 9y²)

First solving for (2x – 3y)(2x + 3y)

Using the identity (a +b) (a–b) = a² – b²

Here a = 2x and b = 3y

= (2x)² – (3y)²

= 4x² – 9y²

Now solving for ( 4x² – 9y² ) (4x² + 9y² )

Again Using the identity (a +b) (a–b) = a² – b²

Here a = 4x² and b = 9y²

= (4x² )² – (9y²)²

= 16 x⁴ – 81 y⁴