## Book: RS Aggarwal - Mathematics

### Chapter: 12. Circles

#### Subject: Maths - Class 10th

##### Q. No. 10 of Multiple Choice Questions (MCQ)

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10
##### If a chord AB subtends an angle of 60° at the center of a circle, then the angle between the tangents to the circle drawn from A and B is

Let us consider a circle with center O and AB be a chord such that AOB = 60°

AP and BP are two intersecting tangents at point P at point A and B respectively on the circle.

To find : Angle between tangents, i.e. APB

As AP and BP are tangents to given circle,

We have,

OA AP and OB BP [Tangents drawn at a point on circle is perpendicular to the radius through point of contact]

So, OAP = OBP = 90°

OAP + OBP + APB + AOB = 360°

90° + 90° + APB + 60° = 360°

APB = 120°

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