Entering polar coordinates and curves
Polar coordinates are entered using a semi-colon: e.g. (3;pi/3)
The default angle measure is degrees. This can be changed in Settings > Graphing (cubic icon).
Polar curves can be entered directly: e.g. r=3+2cos(θ)
NB GeoGebra will plot negative values of r.
You can also use the command Curve[(r;θ),θ,start value, end value]
e.g. Curve[(2 + sin(θ/2); θ), θ, 0, 4pi]