Suppose the vector-valued function r(t) = (f(t),g(t),h(t)) is smooth on an interval containing the point $t_0$. The line tangent to r(t) at t = $t_0$ is the line parallel to the tangent vector r'($t_0$) that passes through (f($t_0$),g($t_0$),h($t_0$)). For the following function, find the line tangent
to the curve at t=$t_0$.
r(t)= (20+ cost,3 + sin 8t,9t): $t_0$=$\frac{\pi}{2}$
