( 2√5 - 3√6 )².tolong pake cara yaa

(2√5 - 3√6)² = (2√5)² - 2 × 2√5 × 3√6 + (3√6)² = 20 - 12√30 + 54 = 20 + 54 -12√30= 74 - 12√30