If x and y are acute angles such that `cosx=13/14 ` and cosy`=1/7` , prove that `(x-y)=pi/3`

If x and y are acute angles such that cos x=(13)/(14) and cosy =(1)/(7), prove that (x-y)=(pi)/(3)

If x and y are acute angles and cosx=(13)/(14)andcosy=(1)/(7) then prove that x-y=-(pi)/(3) .

If x and y are acute angles such that sin x=(1)/(sqrt(5)) and sin y=(1)/(sqrt(10)) prove that x+y=(pi)/(4)

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

If x and y are acute angle such that cosx+"cos" y=(3)/(2) and sin x+"sin" y=(3)/(4) then sin (x+y)=

If sinx+siny=1/2 and cosx+cosy=1 , then tan(x+y)=

(i) Solve: cos(2x + 3y)=1/2, cos(3x+2y) = sqrt(3)/2 (ii) If 0 lt x lt pi, 0 lt y lt pi and cosx + cosy - cos(x+y)=3/2 , prove that x=y=pi/3 .

Find the acute angle between the planes 2x-3y+5z=1 and x-y-z=7 .