bonsoir

exercice  5

A = x² - 12 x + 36 = ( x - 6)²

B = x² - 16 = ( x - 4) ( x + 4)

C = ( 2 x + 1)² - 25 = ( 2 x + 1 - 5) ( 2 x + 1 + 5) = ( 2 x - 4) ( 2 x + 6)

D = x² + 10 x + 25 = ( x + 5 )²

E = 100 + 60 x + 9 x ² = (  3 x + 10 )²

f = 9 - 36 x + 36 x² = ( 6 x - 3 )²

exercice  6

V = 1 501 ² - 1 500 ²

V =  ( n + 1)² - n² = ( n + 1 - n) ( n + 1 + n) =  2 n + 1

donc  1 501 ² - 1 500 ² = 2*1500 + 1 = 3 001

W = 100 000 001² - 100 000 000² = 2 * 100 000 000 + 1 =  200 000 001