 foci - Maple Help

geometry

 foci
 find the foci of an ellipse or a hyperbola Calling Sequence foci(fn, f) Parameters

 fn - (optional) list of two names f - ellipse or hyperbola Description

 • The routine returns a list of two foci of the given ellipse or hyperbola f.
 • If the first optional argument fn is given, the names of the two foci are the two elements of the list fn.
 • See help pages for hyperbola and ellipse for definitions of the foci.
 • Use routine detail for more details on the foci.
 • The command with(geometry,foci) allows the use of the abbreviated form of this command. Examples

 > $\mathrm{with}\left(\mathrm{geometry}\right):$
 > $\mathrm{_EnvHorizontalName}≔x:$$\mathrm{_EnvVerticalName}≔y:$
 > $\mathrm{ellipse}\left(\mathrm{e1},2{x}^{2}+{y}^{2}-4x+4y=0\right):$
 > $\mathrm{foci}\left(\mathrm{e1}\right)$
 $\left[{\mathrm{foci_1_e1}}{,}{\mathrm{foci_2_e1}}\right]$ (1)
 > $\mathrm{map}\left(\mathrm{coordinates},\right)$
 $\left[\left[{1}{,}{-}{2}{-}\sqrt{{3}}\right]{,}\left[{1}{,}{-}{2}{+}\sqrt{{3}}\right]\right]$ (2)
 > $\mathrm{foci}\left(\left[\mathrm{f1},\mathrm{f2}\right],\mathrm{e1}\right)$
 $\left[{\mathrm{f1}}{,}{\mathrm{f2}}\right]$ (3)
 > $\mathrm{foci}\left(\mathrm{e1}\right)$
 $\left[{\mathrm{f1}}{,}{\mathrm{f2}}\right]$ (4)
 > $\mathrm{map}\left(\mathrm{coordinates},\right)$
 $\left[\left[{1}{,}{-}{2}{-}\sqrt{{3}}\right]{,}\left[{1}{,}{-}{2}{+}\sqrt{{3}}\right]\right]$ (5)