Answer: The positive co-terminal angle is
and the negative co-terminal angle is

Step-by-step explanation: We are to find the measures of the two angles, one positive and one negative, that are co-terminal with pi divided by four.
We know that
any two co-terminal angles differ from each other by an integral multiple of

So, to find the positive co-terminal angle, we will add
to
and to find the negative co-terminal angle, we will subtract
from
.
Therefore, the required positive co-terminal angle is given by

And, the required negative co-terminal angle is given by

Thus, the positive co-terminal angle is
and the negative co-terminal angle is
