If has area , with , , and , where , , and are the lengths of the sides opposite…

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

Problem

\triangle PQR

has area

\Delta

, with

a=2

b=\frac72

, and

c=\frac52

, where

a

b

, and

c

are the lengths of the sides opposite angles

P

Q

, and

R

, respectively, then

\frac{2\sin P-\sin 2P}{2\sin P+\sin 2P}

equals: (1)

\frac{3}{4\Delta}

(2)

\frac{45}{4\Delta}

(3)

\left(\frac{3}{4\Delta}\right)^2

(4)

\left(\frac{45}{4\Delta}\right)^5