Foci of an Ellipse

Foci is a point used to define the conic section.  F and G seperately are called "focus", both togeather are called "foci".

 

 

 

 

 

 

 

 

Foci of an Ellipse formula
\( c^2 \;=\; a^2 - b^2  \)
Symbol	English	Metric
\( c \) = length center to focus	\( in \)	\( mm \)
\( a \) = length semi-major axis	\( in \)	\( mm \)
\( b \) = length semi-minor axis	\( in \)	\( mm \)