What is the logarithmic mean of r1 and r2 ?
Correct answer: A. (r1 - r2)/ln(r1/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)
Explanation
The logarithmic mean is obtained by dividing the difference of the two values by the logarithm of their ratio: (r1 − r2)/ln(r1/r2). This form remains positive when the larger radius is assigned as r1.
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