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A function that can be used in Formulas.
sqrt (x)
x.   assert sqrt (0) = 0
   assert sqrt (1) = 1
   assert sqrt (4) = 2
   assert sqrt (9) = 3
   assert (sqrt (2) - 1.41421356237309504880168872420969807856967187537694807317667973799) < 1e-17
© Paul Boersma 2023