Find the area of the shaded region in Fig. 12.20, if radii of the two concentric circles with centre O are 7 cm and 14 cm respectively and `/_A O C= 40^@`

Explanation

To find the area of the shaded region between two concentric circles with radii 7 cm and 14 cm, and an angle \( \angle AOC = 40^\circ \), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Radii and Angle**:
- The radius of the larger circle (R1) = 14 cm
- The radius of the smaller circle (R2) = 7 cm
- The angle \( \angle AOC = 40^\circ \)
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