When the modulus is a real number in the interval , JacobiAmplitude is inverse to EllipticF (both being considered as functions of the first argument).
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This is the derivative.
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This is a series expansion around .
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THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT. SEE THE DOCUMENTATION CENTER FOR THE LATEST INFORMATION.
for Jacobi elliptic functions. 
for an elliptic function to the amplitude 
. 
, then 
. 
is a real number in the interval 
, JacobiAmplitude is inverse to EllipticF (both being considered as functions of the first argument). 
. 
