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In the given figure, AB is the diameter of the circle. Find the value of ∠ACD.

#### Options

25°

45°

60°

30°

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#### Solution

**45°**

**Explanation:**

OB = OD (radius)

∠ODB = ∠OBD

∠ODB + ∠OBD + ∠BOD = 180°

2∠ODB + 90° = 180°

∠ODB = 45°

∠OBD = ∠ACD (Angle subtended by the common chord AD)

Therefore ∠ACD = 45°

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