A) \[{{\text{v}}_{1}}{{\text{v}}_{2}}\]
B) \[{{\text{v}}_{2}}^{2}/{{\text{v}}_{1}}^{2}\]
C) \[({{\text{v}}_{1}}+{{\text{v}}_{2}})/2\]
D) \[2\,{{\text{v}}_{1}}{{\text{v}}_{2}}/({{\text{v}}_{1}}+{{\text{v}}_{2}})\]
Correct Answer: A
Solution :
[d] \[\frac{\frac{x}{2}+\frac{x}{2}}{\frac{x}{2\,{{v}_{1}}}+\frac{x}{2\,{{v}_{2}}}}=\frac{1}{\left( \frac{{{v}_{2}}+{{v}_{1}}}{2\,{{v}_{1}}\,{{v}_{2}}} \right)}=\frac{2\,{{v}_{1}}\,{{v}_{2}}}{{{v}_{1}}\,+{{v}_{2}}}\]You need to login to perform this action.
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