∠A + ∠B = 90°, let us show that

4

If sin 17° = , let us show that sec 10° - sin73° =

5

Let us show that sec²12° -

7

Let us show that cosec²22°cot²68° = sin²22° + sin²68° + cot²68°

8

If ∠A + ∠B = 90°, let us show that,