Answer:
Yes, actually I have five/5
Explanation:
1 - If ABCD is a cyclic quadrilateral, then show that cos A + cos B + cos C + cos D = 0.
2 - Show that, cos^2A + cos^2 (120° - A) + cos^2 (120° + A) = 3/2
3 - If A, B, and C are angles of a triangle, then prove that tan A/2 = cot (B + C)/2
4 - If tan x - tan y = m and cot y - cot x = n, prove that, 1 /m + 1/n = cot (x - y).
5 - If tan β = sin α cos α/(2 + cos^2 α) prove that 3 tan (α - β) = 2 tan α.
Hope this helped!