# Command Symplify

simes shared this problem 14 years ago

Hello!

This is not so important but I noticed that the official manual says that the command:

Simplify [-2 sin (x) cos (x)] gives you a function f (x) = sin (-2 x)

But that's not true, because Geogebra does not simplify the expression in this case. GeoGebra provides exactly what you entered! (version 3.1.260)

With regards

Sime Suljic 1

not here:

typing in german

Vereinfache[-2sin(x)cos(x)] (engl. simplify)

gives exactly

f(x)=sin(-2x)

tested on GeoGebra 3.1.262

best regards

Olaf 1

Vereinfache[-2sin(x)cos(x)] (engl. simplify) gives exactly

f(x)=sin(-2x)

tested on GeoGebra 3.1.262

Sometimes a little strange, but true. For example:

Simplify[(cos(x))²-(sin(x))²] -> cos(-2x)

Simplify[2sin(x)cos(x)] -> -sin(-2x)

Bests, sime 1

ok, i see what you mean.

So, have to teach the symmetry of those functions, so that

that the childs have to simplify again :laughing:

Right, that's not what i want.

Let's wait, if the next release gives an answer.

best regards

Olaf