SOLUTION: If b is the harmonic mean between a and c,then prove that:1/(b-a) +1/(b-c)=1/a+1/c

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Question 1083841: If b is the harmonic mean between a and c,then prove that:1/(b-a) +1/(b-c)=1/a+1/c
Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!
We find the arithmetic mean of  and 

Add them 

Divide by 2:  

Its reciprocal  is the harmonic mean
between a and c, so



Substitute for b in





Multiply numerators and denominators by (a+c)















Factor out 

















Edwin

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