a=sinα+sinβ,b=cosα+cosβ,then sin(α+β)=? what is answer

2ab/a^2+b^2} read alpha =x and beta=yMultiply both a.b=sin x cos x+sin y cos y+sin x cos y + cos x sin y= sin 2x/2 + sin 2y/2 +sin (x+ y)= sin (x+y).cos(x-y) + sin(x+y)By squaring both and adding u will geta^2+b^2= 2+2cos(x-y)By solving above 2 eqn u will get the result

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