हिंदी

`((Sin A- Sin B ))/(( Cos a + Cos B ))+ (( Cos a - Cos B ))/(( Sina + Sin B ))=0`

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प्रश्न

`((sin A-  sin B ))/(( cos A + cos B ))+ (( cos A - cos B ))/(( sinA + sin B ))=0` 

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उत्तर

LHS =`((sin A-  sin B ))/(( cos A + cos B ))+ (( cos A - cos B ))/(( sinA + sin B ))` 

     =`((sinA - sin B )( sinA + sinB )+ ( cos A - cosB )( cosA - cosB))/((cos A+ cos B )( sin A+ sinB))`

    =` (sin^2 A - sin^2 B + cos^2 A - cos^2 B)/( (cos A + cos B )( sinA + sinB))`

   =` 0/((cos A + cos B )( sin A + sinB ))`

   =0 

   =RHS

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अध्याय 13: Trigonometric identities - Exercises 1

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आर.एस. अग्रवाल Mathematics [English] Class 10
अध्याय 13 Trigonometric identities
Exercises 1 | Q 34

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