Question

If x sin cube theta + Y cos cube theta is equal to my sin theta cos theta and as sin theta is equal to me by cos theta prove that X square + Y square is equal to 1

Answer 1

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X sin cube theta +y cos cube theta =sin theta cos theta and x sin theta - y cos theta=0 . Then xsquare + y square

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one month ago

Answers : (1)

xsin3? + ycos3? = sin?cos? 

 

and xsin?=ycos? 

 

Put this value in above equation we get

 

xsin3? + xsin?cos2? = sin?cos? 

xsin?(sin2? + cos2?) = sin?cos? 

x=cos?

so y=sin?

 

hence x2 + y2 = sin2? + cos2? = 1