Each expression simplifies to a constant, a single trigonometric function or a power of a trigometric function. Use fundamental identities to simplify each expression.
NOTE: The argument of the trig functions must be in parentheses (e.g. sin(x)). You also need to use parentheses when raising to some power (e.g. (sin(x))^2 ).

1.  =
2.  =
3. tan (x) cos (x) =
4.  =
5.  =