Question

Am nevoie la punctul c va rog din suflet

Answer 1

Răspuns:

$- \frac{8}{5}$

Explicație pas cu pas:

Salutare !

$\frac{1 + i}{1 - i} \times \frac{1 + 2i}{1 - 2i} + \frac{1 - i}{1 + i} \times \frac{1 - 2i}{1 + 2i}$

$\frac{(1 + i)(1 + 2i)}{(1 - i)(1 - 2i)} + \frac{(1 - i)(1 - 2i)}{(1 + i)(1 + 2i)}$

$\frac{1 + 2i + i + 2i {}^{2} }{1 - 2i - i + 2i {}^{2} } + \frac{1 - 2i - 1 + 2i {}^{2} }{1 + 2i + i + 2i {}^{2} }$

$\frac{ - 1 + 3i}{ - 1 - 3i} + \frac{ - 1 - 3i}{ - 1 + 3i}$

$- \frac{4}{5} - \frac{3}{5} i - \frac{4}{5} + \frac{3}{5} i$

$- \frac{8}{5}$

<<darius>>