A point source S is placed at a distance of 15 cm from a converging lens of focal length 10 cm on its principal axis. Where should a diverging miror of focal length 12 cm be placed to that a real image is formed on the source itself.

Explanation

To solve the problem step by step, we will use the lens formula and the properties of mirrors.

### Step 1: Identify the given values
- Distance of the point source (object distance from the lens), \( u = -15 \) cm (negative because it is on the same side as the incoming light).
- Focal length of the converging lens, \( f = 10 \) cm.
- Focal length of the diverging mirror, \( f_{mirror} = -12 \) cm (negative because it is a diverging mirror).

### Step 2: Use the lens formula to find the image distance from the lens
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