已知复数z满足z•i+z1−i=3+4i(i是虚数单位),则z=(  ) A.3+i B.4-3i C.2-3i D.3-i

问题描述:

已知复数z满足z•i+

z
1−i
=3+4i(i是虚数单位),则z=(  )
A. 3+i
B. 4-3i
C. 2-3i
D. 3-i

z•i+

z
1−i
=3+4i可得z (i+
1
1−i
)=3+4i
z(
2+i
1−i
)=3+4i

所以z=(3+4i)(
1−i
2+i
)=
7+i
2+i
=3−i

故选D.