I attempted to verify graphically the following trig identity:
sin(x) + cos(x) = sqrt(2)*cos(x-%pi/4);
so I did:
(%i1) sin(x)+cos(x)-sqrt(2)*cos(%pi/4-x);
-- skip the output --
(%i2)
plot2d(%o1,[x,0,2*%pi]);
I can send the eps file to anyone interested to see the weird
picture I got.
Here is the result of build_info();
Maxima version: 5.9.0.9beta2
Maxima build date: 14:27 8/11/2004
host type: i686-pc-linux-gnu
lisp-implementation-type: Kyoto Common Lisp
lisp-implementation-version: GCL 2.6.4
*****
Maxima 5.9.0 produced a correct plot. Another observation, the plot
in maxima-5.9.0 came out quite quickly, while maxima-5.9.0.9beta2
took a long time to calculate and produce the plot.
"time(%o2)" shows [13.6].
Milan