Question

计算

(1+i)(1+2i)

1-i

=______．

Answer 1

(1+i)(1+2i)

1-i

=

-1+3i

1-i

=

(-1+3i)(1+i)

(1-i)(1+i)

=

-4+2i

2

=-2+i
故答案为：-2+i．