Parity of Trig Functions
Parity of a Function
The parity of a function says whether a function is even, odd or neither.
To review:
A function is odd if
Odd functions have origin symmetry.
A function is even if
Even functions have -axis symmetry.
Parity for a Trigonometric Function
Using the graph above, since is on the unit circle, it has coordinates:
Consider , on the terminal side of . Drag around the circle and see what you can say about the relationship between and .
Based on the graph...
What about the reciprocal functions?