InterviewSolution
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यदि ` y= sin (tan ^(-1) 2x )` तब सिद्ध कीजिए की `(dy)/(dx)= (2)/((1+4x^(2) )^(3//2) ) ` |
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Answer» `y= sin (tan^(-1) 2x ) ` माना ` tan ^(-1) 2x=t` ` therefore " "y= sin t ` ` rArr " "(dy)/(dt) =cos t ` व ` (dt)/(dx) ={ (1)/((1+ 4x^(2) ))*2} =(2)/((1+4x^(2) ) ) ` हम जानते है की ` " "(dy)/(dx) =((dy)/(dt)xx(dt)/(dx))` ` (dy)/(dt) ` व ` (dt)/(dx) ` के मान रखने पर ` " "(dy)/(dx) ={ cos txx (2)/((1+4x^(2) ))}" "...(1) ` ` t= tan ^(-1) 2xrArr tan t =2x ` ` rArr " "sec t = sqrt (1+tan ^(2) t )= sqrt ( 1+ 4x^(2) )` ` rArr " " cost = (1)/(sqrt (1+ 4x^(2) ) )` समीकरण (1 ) में cos t का मान रखने पर ` (dy)/(dx) ={ (1)/(sqrt (1+4x ^(2)))xx(2)/((1+ 4x^(2))) } =(2)/((1+4x^(2))^(3//2) ) ` |
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