so i've been trying to simplify this equation after using euler's formula. I know what the answer is supposed to be but I can't seem to get it simplified down to it. The equation is

(1-(e^(-jw)))/(1+0.8e^(-jw))+3/(1-0.9e^(-jw)) after using euler's formula it goes to this thanks to our input in the formula: 1-(cos(pi/2)+jsin(pi/2))/(1+0.8(cos(pi/2)+jsin(pi/2)))+3/(1-0.9(cos(pi/2)+jsin(pi/2))), the answer is supposed to 1.77+j0.39 but I'm not sure how to get it down to that from this mess of an equation. any advice or tricks that would help me solve this would be greatly appreciated.