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计算:(1)(-7i+5)-(9-8i)+(3-2i);(2)(4+i)(6-2i)+(7-i)(4-3i);(3)2+2ii+1+i1-i.

题目详情
计算:
(1)(-7i+5)-(9-8i)+(3-2i);
(2)(4+i)(6-2i)+(7-i)(4-3i);
(3)
2+2i
i
+
1+i
1-i
▼优质解答
答案和解析
(1)(-7i+5)-(9-8i)+(3-2i)
=(5-9+3)+(-7+8-2)=-1-i;
(2)(4+i)(6-2i)+(7-i)(4-3i)
=24-2i2-2i+28+3i2-25i
=51-27i;
(3)
2+2i
i
+
1+i
1-i
=
(2+2i)i
i2
+
(1+i)2
(1-i)(1+i)
=
2i-2
-1
+
2i
2
=2-2i+i=2-i