Vineeth12 Years agoi got the answer 1 month ago but how should i post that in the form of a photo(.jpg)
Vineeth12 Years ago{2[2sin(P/7)Cos(P/7)]Cos(2P/7)}/Sin(P/7)-1 =[2sin(2P/7)Cos(2P/7)]/Sin(P/7)-1 =Sin(4P/7) -1 Sin(P/7) =Sin(P-4P/7) -1 Sin(P/7) =Sin(3P/7) -1 Sin(p/7) =Sin(3P/7)-Sin(P/7) Sin(P/7) =2Cos[(3P+P)/2*7]Sin[(3P-P)/2*7] Sin(P/7) =2Cos(2P/7)Sin(P/7) Sin(P/7) =2Cos(2P/7)