If cot A = 4/5, prove that

3

If cos A + cos² A = 1 then (sin²A + sin⁴A) = ?

4

If sin θ = √3/2, then (cosec θ + cot θ) = ?

6

If 2x = sec A and 2/x = tan A, prove that .

7

If √3 tan θ = 3 sin θ, prove that (sin² θ – cos² θ) = 1/3.