the side of a triangle ABC are in A.P.(order being a,b,c) and satisfy 2!/(1!9!) + 2!/(3!7!)+ 1/(5!5!) = 8^a/(2b)! then the value of cosA+cosB is ?? options area. 12/7b. 13/7c. 11/7d. 10/7

Rohit Falake , 10 Years ago

Grade 12th pass