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Foci of a hyperbola
Learn about the foci of the hyperbola: How to find them from the hyperbola's equation and how to find the equation when given the foci.
Sal discusses the foci of hyperbolas and shows how they relate to hyperbola equations.
Given the equation of a hyperbola, find its foci.
Given some features of a hyperbola, find its equation.
Sal proves why, for the general hyperbola equation x^2/a^2-y^2/b^2=1, the focal length f forms the equation f^2=a^2+b^2 with the parameters a and b.