Calculate the moment of intertia of an annular disc about an axis which lies in the plane of the disc and tangential to the inner circle. Mass of the disc is M and its inner radius is `R_1` and outer rad/`R_2`.

Explanation

To calculate the moment of inertia of an annular disc about an axis that lies in the plane of the disc and is tangential to the inner circle, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Geometry of the Annular Disc**:
- The annular disc has an inner radius \( R_1 \) and an outer radius \( R_2 \).
- The axis we are interested in (let's call it axis AB) is tangential to the inner circle and lies in the plane of the disc.

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