Rosen and Morse potential

The Rosen and Morse potential is given by (Eq. 1 ):

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the minimum is located at

$r_{\mathrm {min} }=-\tanh ^{-1}(B/2C)$

as long as Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle |B| \lt 2C} .