A= (2x - 3) ² - (3x + 7 ) (2x-3)
= (2x -3) [ 2x - 3 - (3x +7) ]
= (2x - 3) ( 2x - 3 - 3x - 7]
= (2x - 3) ( -x - 10)
C= 64 t² - 49
= (8t)² - 7²
(on reconnait une identité remarquable)
= (8t + 7) (8t - 7)
D= 0,0004x² - 81
D= (0,02x)² - 9²
D= (0,02 x + 9) (0,02x - 9)
