Find the angles of at least one triangle, one bisector of which is twice bigger than another.
Solution
Let's find an isosceles triangle. Let's pretend that the vertex angle is obtuse. Then let's denote the base angle as (Fig. 49). Then we can easily find values of some angles (Fig. 49):
Let's denote the bisection and the sides as follows: , , , then .
Then . By the law of sines for : . So,
.
The answer of this equality is pretty clear: .
Answer: , , .
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