What is the logarithmic mean of r1 and r2? – McqOptions

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1.	What is the logarithmic mean of r1 and r2?
A.	(r1 - r2)/ln(r1/r2)
B.	(r1 - r2)/ln(r2/r1)
C.	(r2 - r1)/ln(r1/r2)
D.	(r1 - r2)/-ln(r1/r2)
Answer» B. (r1 - r2)/ln(r2/r1)

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