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[tex]2i\overline{z} +z = 3-4i \\ \text{unde }~\overline{z} ~ \text{este } \texttt{conjugatul complex }\text{al lui }z \\ \\ z= a+bi ~~\Longrightarrow~~ \overline{z} = a-bi \\ \\ \text{Rescriem ecuatia: } \\ \\ 2i(a-bi) + (a+bi)=3-4i ~~~~~~~\text{unde a si b sunt necunoscutele} \\ 2ai - 2bi^2 + a + bi = 3 - 4i \\ \text{Dar } ~~i^2 = -1 \\ 2ai - 2b\times (-1) +a + bi = 3 - 4i \\ 2ai + 2b + a +bi = 3-4i [/tex]


[tex]\displaystyle \text{Descompunem ecuatia in doua ecuatii, una imaginara si una reala. } \\ \\ 2ai +bi = -4i ~~~|:i \\ 2b+a=3 \\ --- \\ 2a+b = -4~~|\times (-2) \\ a+2b = 3 \\ --- \\ -4a-2b = 8\\ a+2b = 3 \\ --------- \\ -3a = 11 \\ \boxed{a= -\frac{11}{3}} \\ \\ 2a+b = -4\\ a+2b = 3 ~~|\times (-2)\\ --- \\ 2a+b = -4\\ -2a-4b = -6\\ --------- \\ -3b = -10 \\ \boxed{b = \frac{10}{3}} \\ \\ z=a+bi = \boxed{-\frac{11}{3} + \frac{10}{3}i } [/tex]