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计算:(1)i(2-i)(3+i)(2)设复数z满足z+|z|=2+i,求z的值(3)(2+2i)2(4+5i)(5-4i)(1-i).

题目详情
计算:
(1)i(2-i)(3+i)
(2)设复数z满足z+|
z
|=2+i,求z的值
(3)
(
2
+
2
i)2(4+5i)
(5-4i)(1-i)
▼优质解答
答案和解析
(1)i(2-i)(3+i)=(1+2i)(3+i)=1+7i;
(2)设z=a+bi(a,b∈R),由z+|
z
|=2+i,得
a2+b2
+a+bi=2+i,
a2+b2
+a=2
b=1
,解得
a=
3
4
b=1
,则z=
3
4
+i;
(3)
(
2
+
2
i)2(4+5i)
(5-4i)(1-i)
=
4i(4+5i)
(5-4i)(1-i)
=
-20+16i
1-9i
=
(-20+16i)(1+9i)
(1-9i)(1+9i)
=-2-2i.