Question

Решить уравнение -4х-х^2+1=0

Answer 1

-4x-x²+1=0
x²+4x-1=0
a=1;b=4;c=-1
D=b²-4ac=16+4=20=4*5
x=(-b±√D)/2a=(-4±2√5)/2=-2±√5
x1=-2-√5
x2=-2+√5

Answer 2

-4x - x² + 1 = 0
-x² - 4x + 1 = 0
x² + 4x - 1 = 0
D = 16 + 4 * 1 * 1 = 20
x1 = (-4 + 2√5)/2 = -2 + √5
х2 = (-4 - 2√5)/2 = -2 - √5