Yes, there is a function both even and odd.
\The function is both even and odd function.
If is an even function, then
.
If is an odd function, then
.
The zero function is .
Substitute in
.
Since , the function is an even function.
Multiply each side by negative one.
\Since , the function is an odd function.
Yes, there is a function both even and odd.
\The function is both even and odd function.