Let us prove that cot 12°cot38° cot ° cot52° cot 78° cot 60° =

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

If ∠A + ∠B = 90°, let us show that,

AOB is a diameter of a circle with centre O and C is any point on the circle, joining A.C; B,C; and O, C let us show that

(i) tan∠ABC = cot ∠ACO

(ii) sin²∠BCO + sin²∠ACO = 1

(iii) cosec²∠CAB - 1 = tan²∠ABC

ABCD is a rectangular figure, joining A,C let us prove that

(i) tan∠ACD = cot∠ACB

(ii) tan²∠CAD + 1 =