Arun
Last Activity: 7 Years ago
when we square, we get
sin^2 A + cosec^2 A + 2*sin A* cosecA + cos^2 A + sec^2 A + 2 secA* cosA
as we know we can write,
cosec^2 A = 1 + cot^2 A & sec^2 A = 1+ tan^2 A & sin^2 A+ cos^2 A = 1
& sin A* cosec A = 1 = sec A* cos A
hence
1+1+ cot^2 A + 2 + 1+ tan^2 A + 2
7 + tan^2 A + cot^2 A
hence proved