If `cosx+cosy=3/2+cos(x+y)` then for ` n in I `

If cosx+cosy-cos(x+y)=(3)/(2) then

If cosx=3cosy, then 2tan((y-x)/2)=

If cosx+cosy-cos(x+y)=3/2, then (a) x+y=0 (b) x=2y (c) x=y (d) 2x=y

If cosx=(2cosy-1)/(2-cosy) , where x,y in(0,pi) , then "tan"(x)/(2)"cot"(y)/(2) is equal to

If cosx + cosy + cosz = 0 and sinx + siny + sinz =0 , then show that cos (x-y) + cos(y - z) + cos(z - x) = - 3/2.

If cosx + cosy + cosz = 0 "and" sinx + siny + sinz =0, "then show that" cos (x-y) + cos(y - z) + cos(z - x) = - 3/2.

If 3cosx + 2cos3x=cosy , 3sinx + 2sin3x =siny , then cos2x equals

if x and y are acute angles such that cosx + cosy = 3/2 and sinx + siny = 3/4 then sin(x+y)=

if x and y are acute angles such that cosx + cosy = 3/2 and sinx + siny = 3/4 then sin(x+y)=

If (cosx)^(y)=(cosy)^(x) , then find (dy)/(dx) .