Question

Gasiti nr complex z:
z patrat = 2i

Answer 1

Răspuns:

z²=2i

fie z=a+bi

(a+bi)²=2i

a²+2abi+BI²=2i

a²+2abi-b²=2i=>

a²-b²+2abi=2i=>

[a²-b²=0 a²=b²=> a=√b²=lbl=±b

{2ab=2=>ab=1

a=b=> b²=1=> b=±1   b1==1=> a1=1

z=1+i

Daca a= -bavem

2(-b²)=2

-b²=1

b²= -1   imposibil

Explicație pas cu pas: