In ΔPQR, ∠Q is right angle. If PR = √5 units and PQ – RQ = 1 unit, then let us determine the value of cosP – cosR.

If then let us determine the values of tan θ + cot θ and tan θ – cot θ and from these let us write the value of tan θ.

If then let us write by calculating, the value of (sec⁴ – tan⁴ θ).

In ΔXYZ, ∠Y is right angle. If XY = 2√3 units and XZ – YZ = 2 units then let us determine the values of (secX - tanX).

Let us eliminate ‘θ’ from the relations :

x = 2 sin θ, y = 3 cos θ