bonjour
20 a² - ( 2 + 3 a ) = 20 a² - 2 - 3 a
- ( 20 a² + 3 ) = - 20 a² - 3
- 10 a ( 2 a + 3 ) = - 20 a² - 30 a
- 5 a ( 5 a + 6 ) = - 25 a² - 30 a
10 ( 10 c²+ d ) + u = 100 c² + 10 d + u
( 2 c + 3 ) ( 5 a + 4 c ) = 10 ac + 8 c² + 152 a + 12 c
( 3 x + 5 )² = 9 x² + 30 x + 25
