Nếu \({\log _{12}}6 = a;{\rm{ }}{\log _{12}}7 = b\...

Câu hỏi: Nếu \({\log _{12}}6 = a;{\rm{ }}{\log _{12}}7 = b\) thì :

A. \({\log _2}7 = \frac{a}{{a - 1}}\)

B. \({\log _2}7 = \frac{a}{{1 - b}}\)

C. \({\log _2}7 = \frac{a}{{1 + b}}\)

D. \({\log _2}7 = \frac{b}{{1 - a}}\)