Which type of lens forms always a virtual image ?

Explanation

To determine which type of lens always forms a virtual image, we can follow these steps:

### Step 1: Understand the Types of Lenses
There are two main types of lenses: **convex lenses** and **concave lenses**.

### Step 2: Analyze Convex Lenses
Convex lenses are thicker in the middle and can converge light rays. They can form both real and virtual images depending on the position of the object relative to the lens. When the object is placed within the focal length of a convex lens, it forms a virtual image. However, it does not always form a virtual image.

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