If sin α = −3/5, where π < α < 3π/2, then the value of cos α/2 is:2
2. If sin A = 2/3 and cos A < 0, find the value of tan 2A.
A car is running on a circular path of radius equal to double the arc of the circle travelled by the car. The angle subtended by the car on the centre of the path is: