Question

设t是实数，且

t

1- 3 i

+

1- 3 i

2

是实数，则t=______．

Answer 1

∵

t

1- 3 i

+

1- 3 i

2

=

t(1+ 3 i)

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

+

1- 3 i

2

=

t+ 3 ti

4

+

2-2 3 i

4

=

2+t+(t-2) 3 i

4

它是实数∴t-2=0，即 t=2
故答案为：2