Bonsoir
A (x) = ( 3 x - 5 )² - ( 3 x - 5 ) ( 8 x - 2 )
A (x) = 9 x² - 30 x + 25 - ( 24 x² - 6 x - 40 x + 10 )
A (x) = 9 x² - 30 x + 25 - 24 x² + 46 x - 10
A (x) = - 15 x² + 16 x + 15
A (x) = ( 3 x - 5 ) ( 3 x - 5 - 8 x + 2 )
A (x) = ( 3 x - 5 ) ( - 5 x - 3 )
A ( 2/7 ) = ( 6/7 - 5 ) ( - 10 /7 - 3 )
A ( 2/7 ) = ( 6 /7 - 35/7 ) ( - 10 /7 - 21/7 )
A ( 2 /7 ) = - 29/7 x - 31 /7 = 899/49
fais pareil avec - 3 /5