问题
填空题
已知复数z满足(1+2i)z=5(i为虚数单位),则z=______.
答案
∵(1+2i)z=5,∴z=
=5 1+2i
=5(1-2i) (1+2i)(1-2i)
=1-2i,5(1-2i) 5
故答案为 1-2i.
已知复数z满足(1+2i)z=5(i为虚数单位),则z=______.
∵(1+2i)z=5,∴z=
=5 1+2i
=5(1-2i) (1+2i)(1-2i)
=1-2i,5(1-2i) 5
故答案为 1-2i.