本题计算过程如下:(1-2i/3-4i)-(2-i/5i)=(1-2i)(3+4i)/(3-4i)(3+4i)-(2-i)(5i)/(5i)^2=(1-2i)(3+4i)/25+(2-i)(5i)/25=(11-2i)/25+(5+10i)/25=(16/25)+(8i/25)
