bonjour
f (x) = 4 ( x - 2 )² - 100
f (x) = 4 ( x² - 4 x + 4 ) - 100
f (x) = 4 x² - 16 x + 16 - 100 = 4 x² - 16 x - 84
f (x) = 4[ ( x - 2 - 10 ) ( x - 2 + 10 ) ]
f (x) = 4[ ( x - 12) ( x + 8 ) ]
f ( 0) = 4 * 0 - 16 * 0 - 84 = - 84
f ( 2) = 4 * 2² - 16 *2 - 84 = 16 - 32 - 84 = - 100
f (x) = 4 x²
4 ² - 16 x - 84 = 4 x²
4 x² - 4 x² - 16 x - 84 = 0
- 16 x - 84 = 0
- 16 x = 84
x = - 5.25
4 x² - 16 x - 84 = - 150
4 x² - 16 x - 84 + 150 = 0
4 x² - 16 x + 66 = 0
Δ = 256 - 4 ( 4 * 66) = 256 - 1 056
Δ < 0 donc pas de solution
