Posted by marley on Monday, June 6, 2011 at 11:53pm.
please solve these if possible
Q1. If sinx +siny=3(cosycosx) then the value of sin3x/sin3y.
Q2. If sina ,cosa,and tan a are in g.p.then cos cubea+cos square a is equal to

maths (trigonometry)  Anonymous, Tuesday, June 7, 2011 at 1:43am
Q1.
From the given relation, we can write, 3 cos x + sin x = 3 cos y  sin y
put r cos ƒ¿=3 and r sin ƒ¿ = 1 , then we get , r = ã 10, tanƒ¿= 1/3
so r cos ( x  ƒ¿) = r cos (x+ƒ¿)
x =  y or x = }(y+ƒ¿)
clearly x =  y satisfies the equation
therefore, x =  y
so 3x = 3y
sin 3x = sin (3y) =  sin 3y
sin 3x / sin 3y = 1

maths (trigonometry)  Anonymous, Tuesday, June 7, 2011 at 1:44am
ƒ¿= Greek letter Alpha

maths (trigonometry)  Mgraph, Tuesday, June 7, 2011 at 9:58am
Q2)Because sina, cosa, tana  g.p.
cos^2(a)=sina*tana=sin^2(a)/cosa
cos^2(a)=(1cos^2(a))/cosa
cos^3(a)=1cos^2(a)
Answer This Question
Related Questions
 Math  Suppose f(x) = sin(pi*cosx) On any interval where the inverse function y...
 Trigonometry  Prove the following trigonometric identities. please give a ...
 Math help again  cos(3π/4+x) + sin (3π/4 x) = 0 = cos(3π/4)cosx...
 trig  I need to prove equality. a) (sina + cosa)^2 1 / ctga  sinacosa = 2tg^...
 Trig.......  I need to prove that the following is true. Thanks (2tanx /1tan^x...
 Maths  Hi, can someone give me the answer to this question: secAtanA=1/4. Find...
 Trigonometry.  ( tanx/1cotx )+ (cotx/1tanx)= (1+secxcscx) Good one! Generally...
 math (trig)  i have some problems doing trig the first one is: Show that cos(x/...
 maths  trigonometry  I've asked about this same question before, and someone ...
 Trigonometry  4. Find the exact value for sin(x+y) if sinx=4/5 and cos y = 15/...
More Related Questions