Question
The relation among u, v and f for a mirror is:

Answer

  1. $\text{f}=\frac{\text{uv}}{\text{u+v}}$
Explanation:
As we know,
$\frac{1}{\text{f}}=\frac{1}{\text{v}}+\frac{1}{\text{u}}$
$\frac{1}{\text{f}}=\frac{\text{u+v}}{\text{uv}}$
$\text{f}=\frac{\text{uv}}{\text{u+v}}$

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