复数 设x,y属于R,且[x /(1-i) ] +[y /(1-2i)]=5/(1-3i) ,求x+y的值

x/(1-i)]+[y/(1-2i)]=[5/(1-3i)]
即
[x(1+i)/(1-i)(1+i)]+[y(1+2i)/(1-2i)(1+2i)]=[5(1+3i)/(1-3i)(1+3i)]
即
5x+5xi+2y+4yi=5+15i
即
(5x+2y)+(5x+4y)i=5+15i
所以得到
5x+2y=5
5x+4y=15
所以
x=-1
y=5
所以x+y=5/2