Q13 of 90 Page 8

Mark the Correct alternative in the following:

If then sin 3x + sin 3y =


sin x + sin y = √3 (cos y – cos x)






⇒ x + y = 0 or


⇒ x = -y


or


⇒ x = -y


or


Putting these values of x in sin 3x + sin 3y,


For x = -y


sin 3x + sin 3y


= sin 3(-y) + sin 3y


= -sin 3y + sin 3y


= 0


For


sin 3x + sin 3y



= sin (3y + π) + sin 3y


= -sin 3y + sin 3y


= 0


So, sin 3x + sin 3y = 0 (Ans)

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