bonsoir
a = ( 4 x + 10)² + ( 2 x + 5) ( - 4 x - 2)
a = 16 x² + 80 x + 100 - 8 x² - 4 x - 20 x - 10
a = 8 x² + 56 x + 90
pour x = 3
a = 72 + 168 +90 = 330
pour x = - 2/3
a = 8 ( - 2/3)² + 56( - 2/3) + 90
a = 8 * 4/9 - 112/3 + 90
a = 32/9 - 112/3 + 90
a = 32/9 - 336/9 + 810/9
a = 506/9
