題組內容

Question 5. [Maximum mark: 9] 
A water truck tank which is 3 meters long has a uniform cross-section in the shape of a major segment. The tank is divided into two equal parts and is partially filled with water as show in the following diagram of the cross-section. The centre of the circle is O, the angle AOB is ? radians, and the angle AOF β is ? radians629d91f155432.jpg

(a) Find an expression for the volume of water V, in m3 , in the left part of the water tank in terms of β?.