bonjour
f (x) = x² - 3 x
il suffit de remplacer x par sa valeur
f ( - 1.2 ) = ( - 1.2 )² - 3 * - 1.2 = 1.44 + 3.6 = 5.04
f ( - 1 ) = 1 - 3 * - 1 = 1 + 3 = 4
f ( - 0.8 ) = 0.64 - 3 * - 0.8 = 0.64 + 2.4 = 3.04
f ( - 0.6 ) = 0.36 - 3 * - 0.6 = 0.36 + 1.8 = 2.16
f ( 1.8) = 1.8²- 3 * 1.8 = 3.24 - 5.4 = - 2.16
f ( 2) = 4 - 3 *2 = 4 - 6 = - 2
