I have a couple of questions that i cant figure out to save myself =/

1.these are expressing in the form a+ib $\displaystyle \frac{1}{(2+i)(z+1)} = 5-3i $

i got z= -1/14 + i/14

2. $\displaystyle 2z^2=6iz + 3$

didnt know how to do this.

3. $\displaystyle (z)(zcon)+2(z-zcon)=10 +2i$ (where zcon is the conjugate of z)

okay and theres:

"$\displaystyle 1-zi$ is the root of the equation

$\displaystyle z^2+(i+1)z+k=0$

find the other root and the value of k."

now i assume you use the $\displaystyle \Delta$ but im not sure.

im sorry theres so many but i need the help.

also if this isnt the correct forum also sorry as there was a similar problem listed here too