bonsoir
g (t) = 2 t² - t - 3
g (t) = ( 2 t - 3 ) ( t + 1 ) = 2 t² + 2 t - 3 t - 3 = 2 t² - t - 3
g (t ) = 2 ( t - 1/4 )² - 25/8 = 2 ( t² - 2 t /4 + 1/16 ) - 25 /8
= 2 t² - 4 t/4 + 2/16 - 25/8
= 2 t² - t + 2/16 - 50/16 = 2 t² - t - 48/16 = 2 t² - t - 3
g ( -10) = 2 ( - 10 )² - ( -10 ) - 3 = 200 + 10 - 3 = 207
g ( 1/4 ) = 2 ( 1/4 )² - 1/4 - 3 = 2/16 - 4/16 - 48/16 = - 50/16 = - 25/8
( 2 t - 3 ) ( t + 1 ) = 0
t = 3/2 ou - 1
2 t² - t - 3 = - 3
2 t² - t - 3 + 3 = 0
t ( 2 t - 1 ) = 0
t = 0 ou 1/2
