|  | ◆ Sqrt1pm1()
      
        
          | Function Sqrt1pm1 | ( | X As | Double, |  
          |  |  | Optional Info As | Long |  
          |  | ) |  |  |  
sqrt(1 + x) - 1  PurposeEvaluates sqrt(1 + x) - 1 accurately in the sense of relative error when x is very small.
 ReturnsDoublesqrt(1 + x) - 1.
 Parameters
  
    | [in] | X | Argument x. (X >= -1) |  | [out] | Info | (Optional) = 0: Successful exit.
 = -1: The argument X had an illegal value. (X < -1)
 = 1: Floating point range error.
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 Referenceboost/math/special_functions 
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