In a , let , , and . Which of the following statement(s) is(are)…

MATHEMATICS · Multi correct · A Level · Mathematics · Trigonometry · Trigonometry

Problem

In a

\triangle ABC

, let

BC=1

AC=2

, and

\angle C=30^\circ

. Which of the following statement(s) is(are) correct? (1)

2\sin A=\sin B

(2) The length of side

AB

equals

5-2\sqrt{3}

(3) The measure of

\angle A

is less than

30^\circ

(4) The circumradius of

\triangle ABC

is equal to the length of side

AB