Posted by marley on Monday, June 6, 2011 at 11:53pm.
please solve these if possible
Q1. If sinx +siny=3(cosy-cosx) 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
From the given relation, we can write, 3 cos x + sin x = 3 cos y - sin y
put r cos ¿=3 and r sin ¿ = 1 , then we get , r = ã 10, tan¿= 1/3
so r cos ( x - ¿) = r cos (x+¿)
x = - y or x = }(y+¿)
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
¿= Greek letter Alpha
- maths (trigonometry) - Mgraph, Tuesday, June 7, 2011 at 9:58am
Q2)Because sina, cosa, tana - g.p.
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