how I can I get MAPLe to simplify this to beta (inside a larger calculation)

simplify(arctan(sin(beta)/cos(beta)),trig) assuming beta<Pi/2,beta>0;

I am aware (and use this a lot, eeasiest formula for a sawtooth function plot).
plot(arctan(tan(x)),x=0..20);

Subject: export animation ---> beamer / pdf? is in the newer releases "animated gif" still the only option for exporting MAPLE animations? if so, what is the best way of getting this into a beamer (via latex/pdflatex and acroread) presentation -- prefer- rably portable to any machine that has acro-read installed (want to bring the talk on a memory stick, don't bring the laptop -- yet not worry about installed helpers). so far my pdflatex accepts in beamer mp4 movies, and I can convert single frames of gif to pdf, but not animations.

I have still been using mostly release 8, but was wondering whether MAPLE 10 now can do things standard in MATLAB, JAVA: Is there a way in release 10 (maybe via maplets?) to use the mouse for extract the coordinates of a point from a maple-plot [[ e.g. want to use initialize a dsolve() by graphically selecting the initil data.]] going further, is there a way to "draw" a curve on a maple plot using the mouse -- and get the coordinates of points along the curve back into the worksheet )(e.g. as an array that can be further manipulated)?