Choose the correct option and justify your choice:
(A) tan 90° (B) 1 (C) sin 45° (D) 0.
Choose the correct option and justify your choice:
sin 2A = 2 sin A is true when A =
(A) 0° (B) 30° (C) 45° (D) 60°
Choose the correct option and justify your choice:
(A) cos 60° (B) sin 60° (C) tan 60° (D) sin 30°.