Basic formula of logarithmic function It is known that log10 / 2 = A and log10 / 3 = B. try a and B to denote log12 / 5

log12/5
=(lg5)/(lg12)
=[lg(10/2)]/[lg(3*2*2)]
=(1-lg2)/(lg3+2lg2)
=(1-a)/(2a+b)
The main use of bottom formula, another bracket too much to see more trouble!

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