Sa se determine numere complexe "z" care verifica relatia
a) z (patrat)+2i=0
b)z (patrat)+3-4i=0


Răspuns :

a) Δ=b²-4ac=4i²-0=4*(-1) = -4

z1,z2=(-b+i√-Δ)/2a

z1=(-2+4i)/2= 2(-1+2i)/2= -1+2i

z2=(-2-4i)/2= 2(-1-2i)/2= -1-2i


b) z²-4i+3=0

Δ=b²-4ac=16i²-12= -16-12= -28

z1,z2=(-b+i√-Δ)/2a

z1=(4i+2V7)/2=2(2i+V7)/2= 2i+V7

z2= 2i-V7