Odpowiedź:
x = 0 v x = - 1 v x = 5.
Szczegółowe wyjaśnienie:
x⁴ - 4x³ - 5x² = 0
x² (x² - 4x - 5 ) = 0
x² = 0 , => x = 0
x² - 4x - 5 = 0
a = 1 , b = - 4 , c = - 5
∆ = b² - 4 * a * c
∆ = (-4)² - 4 * 1 * (-5) = 16 + 20 = 36
√∆= 6
x1 = (-b - √∆)/2a
x1 = (4 - 6)/2 = - 2/2 = - 1
x2 = (-b +√∆)/2a
x2 = (4 + 6)/2 = 10/2 = 5
Odp : x = 0 v x = - 1 v x = 5.
