bonsoir
f (x) = - 2 x² - 3
A ( 5) = - 2 *5² - 3 = - 50 - 3 = - 53 donc A ∈ courbe
B ( - 5 ) = - 2 ( - 5 )² - 3 = - 50 - 3 = - 53 donc B ∈ courbe
C ( - 4 ) = - 2 ( - 4 )² - 3 = - 32 - 3 = - 35 donc C ∉ courbe
D ( - 3 ) = - 2 ( - 3 )² - 3 = - 18 - 3 = - 21 donc D ∉ courbe