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RealRootRefine

refine a real root of a univariate polynomial
Syntax 

RealRootRefine(Root:RECORD, Precision:RAT):RECORD

Description
This function computes a refinement of a real root of a univariate polynomial over Q to the desired precision (width of isolating interval). The starting root must be a record produced by RealRoots .

Example 
  RR := RealRoots(x^2-2);
  RealRootRefine(RR[1], 1/2);
Record[ CoeffList = [-8, 1456, -712], Inf = -91/64, Sup = -45/32]
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  RR := [RealRootRefine(Root, 10^(-20)) | Root In RR];
  FloatStr(RR[1].Inf);
-1.414213562*10^0
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See Also