Given cos x = -3/7, with pi < x < 3pi/2, find sin 2x

[JAsh]

given cosx= -3/7 , pi < x < 3pi/2

determine the exact value of sin2x

 

[pka]

From the given it is easy to see that \(\displaystyle \sin (x) = - \frac{{\sqrt {40} }}{7}\).