Real Analytic Function
A real function is said to be analytic if it possesses derivatives of all orders and agrees with its Taylor series in a neighborhood of every point.
See also
Analytic Function, Real FunctionExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Real Analytic Function." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RealAnalyticFunction.html