Remarks on Unimodular Rows

Part of the Developments in Mathematics book series (DEVM, volume 18)


If (a,b,c) is a unimodular row over a commutative ring A and if the polynomial \({z}^{2} + bz + ac\) has a root in A, we show that the unimodular row is completable. In particular, if 1∕2∈A and b 2−4ac has a square root in A, then (a,b,c) is completable.


Exact Sequence Line Bundle Algebraic Group Maximal Ideal Commutative Ring 


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The first author was partially supported by a grant from the NSA.


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Copyright information

© Springer New York 2010

Authors and Affiliations

  1. 1.Department of MathematicsWashington University in St. LouisSt. LouisUSA
  2. 2.Department of MathematicsUniversity of ChicagoChicagoUSA

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