[tex]z=\frac{1}{4+3i}+\frac{(2-i)^2}{1+i}-\frac{i}{4i-3}+\frac{6}{2-i}[/tex]
[tex]z=\frac{4-3i}{(4-3i)(4+3i)}+\frac{(4-4i+i^2)\cdot (1-i)}{(1-i)(1+i)}-\frac{i(-4i-3)}{(-3+4i)(-3-4i)}+\frac{6(2+i)}{(2+i)(2-i)}[/tex]
[tex]z=\frac{4-3i}{4^2-3^2i^2}+\frac{(4-4i-1)(1-i)}{1^2-i^2}-\frac{-4i^2-3i}{(-3)^2-4^2i^2}+\frac{12+6i}{2^2-i^2}[/tex]
[tex] z=\frac{4-3i}{16+9}+\frac{(3-4i)(1-i)}{1+1}-\frac{-4\cdot (-1)-3i}{9+16}+\frac{12+6i}{4+1}[/tex]
[tex] z=\frac{4-3i}{25}+\frac{3-3i-4i+4i^2}{2}-\frac{4-3i}{25}+\frac{12+6i}{5}[/tex]
[tex] z=\frac{3-4-7i}{2}+\frac{12+6i}{5}[/tex]
[tex]z=\frac{5(-1-7i)}{10}+\frac{2(12+6i)}{10}[/tex]
[tex]z=\frac{-5-35i+24+12i}{10}[/tex]
[tex]z=\frac{19-23i}{10}[/tex]
[tex]z=\frac{19}{10}+\frac{-23}{10}i[/tex]
[tex]\Rightarrow Im(z)=\frac{-23}{10}[/tex]