Question:
If $(1+i) z=(1-i) \bar{z}$, then show that $z=-i \bar{z}$.
Solution:
$(1+i) z=(1-i) \bar{z}$
$\Rightarrow \frac{z}{\bar{z}}=\frac{1-i}{1+i}$
$\Rightarrow \frac{z}{\bar{z}}=\frac{1-i}{1+i} \times \frac{1-i}{1-i}$
$\Rightarrow \frac{z}{\bar{z}}=\frac{1+i^{2}-2 i}{1-i^{2}}$
$\Rightarrow \frac{z}{\bar{z}}=\frac{1-1-2 i}{1+1}$ $\left[\because i^{2}=-1\right]$
$\Rightarrow \frac{z}{\bar{z}}=\frac{-2 i}{2}$
$\Rightarrow \frac{z}{\bar{z}}=-i$
$\Rightarrow z=-i \bar{z}$
Hence, $z=-i \bar{z}$.