If , , and are interior angles of such that ( A+ B+ C)^2+( A+ B+ C)^2=9, then the…

MATHEMATICS · Single correct · A Level · Mathematics · Trigonometry · Trigonometry

Problem

A

B

, and

C

are interior angles of

\triangle ABC

such that

(\cos A+\cos B+\cos C)^2+(\sin A+\sin B+\sin C)^2=9,

then the number of possible triangles is (1)

0

(2)

1

(3)

3

(4) Infinite