Please provide detailed steps on how to factor the following

Please provide detailed steps on how to factor the following polynomial

12m²n² - 8mn + 1

Solution

This is a trinomial in mn. To make it look more familiar , let x = mn then

12 x² - 8 x + 1 this is not difficult to factor - it is just

(6 x -1) (2 x -1)

putting back mn for x we get

( 6 mn -1) (2 mn -1)