If the radius of the circumcircle of an isosceles triangle PQR is equal to PQ (= PR),then the angle P, is

Explanation

To solve the problem, we need to find the angle P in the isosceles triangle PQR, given that the radius of the circumcircle (R) is equal to the length of the sides PQ and PR.

### Step-by-Step Solution:

1. **Understanding the Triangle**:
We have an isosceles triangle PQR where PQ = PR. Let the lengths of these sides be denoted as a. The circumradius R is given to be equal to a (R = PQ = PR).

2. **Using the Circumradius Formula**:
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