The harmonic mean of is 1/ a and 1/b is

A) a+b/2
B) ab/2ab
C) ab/2(a+b)
D) 2/ a+b

For a&b it is 2ab/a+b, what is for 1/a and 1/b

Please answer it and strictly don't spam

Will mark BRAINLIEST if correct answer is given to me
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