计算 5(4+i)2i(2+i)=_.
问题描述:
计算
=______. 5(4+i)2
i(2+i)
答
=5(4+i)2
i(2+i)
=5(16+8i+i2) 2i+i2
5(15+8i) −1+2i
=
5(15+8i)(−1−2i) (−1+2i)(−1−2i)
=
5(1−38i) 5
=1-38i
故答案为:1-38i