Dear,
cosx/{[2x/(2n+1)
] +1/2 } can be written as
2(2n+1)
cosx/[4x+(2n+1)
]
now [4x+(2n+1)
]=t
you will get the form cos({t/4}-A)/t where A=(2n+1)
/4
expand the cos as cos(C+D) = cosC.cosD-sinCsinD
and i think now you can solve the further , ask if doubt any.
Moderation Team
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0
] +1/2 } = ?
