JEE Advanced 2012 Paper 2 Mathematics Q2

Mathematics

Problem

Let

PQR

be a triangle of area

\Delta

with

a=2

b=\dfrac72

and

c=\dfrac52

, where

a

b

and

c

are the lengths of the sides of the triangle opposite to the angles at

P

Q

and

R

respectively. Then

\dfrac{2\sin P-\sin2P}{2\sin P+\sin2P}

equals