Question

prove the following.

Answer 1

ah .. man that's classic problem!!

Answer 2

manipulate angle by half .. 2 sin (x/2) cos (x/2) you should be able to get it.

Answer 3

although somebody mentioned it can be proved using complex numbers, i didn't get it.

Answer 4

lol......that integral again...:D

Answer 5

well mahmit2012 had posted it first ... i learned it from there. seems it has other many interesting forms.

Answer 6

someone asked it already ? ..@mukushla

Answer 7

yep ... couple of times.

Answer 8

ok i was going through calculus book i found this as challenging . i did try but was unable to solve it.!

Answer 9

let me write a quick sol