Question

Решите уравнение:
х^2-2х-1=0
4х^2-8х-1=0
х^2-2х-4=0

Answer 1

1)D=4+4=8
x1=(2-2√2)/2=1-√2
x2=1+√2
2)D=64+16=80
x1=(8-4√10)/8=1-0,5√10
x2=1+0,5√10
3)D=4+16=20
x1=(2-2√5)/2=1-√5
x2=1+√5