5.1 In the diagram below, P(k ; 24) is a point in the second quadrant such that OP = 25 units. N is a point on the positive x-axis and PÔN = θ.
WITHOUT calculating the size of 0, determine the value of the following:
5.1.1 k (2)
5.1.2 tan θ (1)
5.1.3 sina if θ + a = 360o (3)
5.1.4 cos2 – sin2 a (3)
5.2 Simplify WITHOUT using a calculator: (5)
5.3 Prove the identity: (4)
5.4 Determine the general solution of 
(6)
[24]