Question 20658
First, remove the parentheses then collect like-terms:

{{{1/3 + (2/3)i + 1/3 - (5/6)i}}}
{{{1/3 + 1/3 + (2/3)i - (5/6)i}}}
{{{2/3 + (4/6)i - (5/6)i}}}
{{{2/3 - (1/6)i}}}