Question

Determinati z ∈ C daca 2z(conjugat) +z=3+4i

Answer 1

Fie z=a+bi numarul complex.
z conjugat=a-bi.
2z conjugat + z=3+4i
2(a-bi)+a+bi=3+4i
2a-2bi+a+bi=3+4i
3a-bi=3+4i
3a=3 => a=1
-b=4 => b=-4
z=1-4i.