To determine which trigonometric functions include the point
-
:- Substitute
: - At
, (not ).
- Substitute
-
:- Substitute
: - At
, .
- Substitute
-
:- Substitute
: - At
, .
- Substitute
-
:- Substitute
: - At
, .
- Substitute
-
:- Substitute
: - At
, (not ).
- Substitute
Summary of results:
gives at . gives at . gives at .
Therefore, the functions that include the point