Express each of the following in the form (a + ib):
$\frac{(3-4 i)}{(4-2 i)(1+i)}$
Given: $\frac{3-4 i}{(4-2 i)(1+i)}$
Solving the denominator, we get
$\frac{3-4 i}{(4-2 i)(1+i)}=\frac{3-4 i}{4(1)+4(i)-2 i(1)-2 i(i)}$
$=\frac{3-4 i}{4+4 i-2 i-2 i^{2}}$
$=\frac{3-4 i}{4+2 i-2(-1)}$
$=\frac{3-4 i}{6+2 i}$
Now, we rationalize the above by multiplying and divide by the conjugate of 6 + 2i
$=\frac{3-4 i}{6+2 i} \times \frac{6-2 i}{6-2 i}$
$=\frac{(3-4 i)(6-2 i)}{(6+2 i)(6-2 i)}$
Now, we know that
$(a+b)(a-b)=\left(a^{2}-b^{2}\right)$
So, eq. (i) become
$=\frac{(3-4 i)(6-2 i)}{(6)^{2}-(2 i)^{2}}$
$=\frac{3(6)+3(-2 i)+(-4 i)(6)+(-4 i)(-2 i)}{36-4 i^{2}}$
$=\frac{18-6 i-24 i+8 i^{2}}{36-4(-1)}\left[\because{\mathrm{i}}^{2}=-1\right]$
$=\frac{18-30 i+8(-1)}{36+4}$
$=\frac{18-30 i-8}{40}$
$=\frac{10-30 i}{40}$
$=\frac{10(1-3 i)}{40}$
$=\frac{1-3 i}{4}$
$=\frac{1}{4}-\frac{3}{4} i$