Question

1)x^{2} -x+4=0

3)-4 x^{2} +4x-5=0

2)3 x^{2} -2x-5=0

Answer 1

1) $x^{2} -x+4=0$
Δ=1-16==-15
 x1 =(1-√-15)/2=(1-i√ 15 )/2=
x1 =(1+√-15)/2=(1+i√ 15 )/2=


3) -4x²+4x-5=0
Δ=-64
 x1 =(-4-√-64)/-8=1/2+i
  x2 =(-4+√-64)/-8=1/2-i

2)
3x²-2x-5=0
Δ=2²-4[(-5)×3]
Δ=4+60=64
 x1 = -1
 x2= 5/3 = 1.667