A) 2
B) \[\frac{PQ}{(P+Q)}\]
C) \[\frac{(P+Q)}{PQ}\]
D) none of these
Correct Answer: A
Solution :
Key Idea: If H is harmonic mean between a and b, then\[H=\frac{2ab}{a+b}\] Given H is harmonic mean between P and Q. \[\therefore \] \[H=\frac{2PQ}{P+Q}\] \[\Rightarrow \] \[\frac{H}{P}=\frac{2Q}{P+Q}\] ?.. (i) Also, \[\frac{H}{Q}=\frac{2P}{P+Q}\] ?. (ii) \[\therefore \] \[\frac{H}{P}+\frac{H}{Q}=\frac{2(P+Q)}{P+Q}=2\]You need to login to perform this action.
You will be redirected in
3 sec