Bonjour,
rappel :
- ( a + b )² = a² + 2ab + b²
- ( a - b )² = a² - 2ab + b²
x² + 18x + 81 = ( x + 9 )²
49x² - 56x + 16 = ( 7x - 4² )
25x² + 80x + 64 = 5x + 8²
100x² - 60x + = ( 10x - 3 )²
x² - x + 1/4 = ( x - 1/2 )²
4x² + 20x + 25 = ( 2x + 5 )²
16x² + 80x + 100 = ( 4x + 10 )²
Bonne journée
