In the adjoining figure, PQR is a right triangle right angled at Q. If PQ = 4 cm and PR = 8 cm then ∠P is equal to

1. 60°

2. 45°

3. 30°

4. 15°

Find the values of :

sin² 60° - cos² 45° + 3 tan² 30°

Find the values of :

sec 30° tan 60° + sin 45° cosec 45° + cos 30° cot 60°

Taking A = 30°, verify that

(i) cos⁴ A - sin⁴ A = cos 2A

(ii) 4 cos A cos (60° - A) cos (60° + A) = cos 3A.