Question

Express the following in terms of angle between 0° and 45°
1. Sin 80°+ Cos 72°
2. Tan 62°+ Sec 56°

Answer 1

Answer:

sin 80° = sin (90 - 10) = cos 10°

cos 72° = cos (90-18) = sin 18°

therefore sin 80° + cos 72°

=> cos 10° + sin 18°

tan 62° = tan(90-28) = cot 28°

sec 56° = sec(90-34°) = cosec 34°

therefore tan 62° + sec 56°

=> cot 28° + cosec 34°