An admixture of a right-handed b → c current in the semileptonic weak decays of the B mesons would give a significantly different contribution to the inclusive rate of the decays B → lvXc as compared to the exclusive decay B → D*lv at zero recoil. Thus a difference in the values of |Vcb| extracted from the data on these two types of decay would measure such admixture. The present marginal mismatch in determination of |Vcb| by the two methods can be interpreted as corresponding to 9R/9L ≈ 0.14 ± 0.18.
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I am thankful to M. Shifman, N. Uraltsev and Y. Kobota for the useful discussions of theoretical and experimental aspects of the problem discussed here. This work was supported, in part, by the DOE grant DE-AC02-83ER40105.