tolong pakai cara dengan baik

2. =3x² + 2x² - x + 2
= 5x² - x + 2

1) ( x + 3)( x - 3)
= x² + 3x - 3x - 9
= x² - 9

2) ( 2x - 1)( x + 3)
= 2x² - x + 6x - 3
= 2x² + 5x - 3

3) ( 3a / 5a ) × ( 2ab / 3b )

= ( 3a )( 2ab )
--------------------
( 5a )( 3b )

= 6a²b
------------
15ab

= 2a
--------
5