Find derivative of the following functions (it is to be understood that a, b, c, d, p, q, r and s are fixed non-zero constants and m and n are integers): `(x + cos x) ( x - t a n x)`

Explanation

Let `f(x)=(x + cos x) ( x - t a n x)`


Let `u=(x + cos x), v=( x - t a n x)`


using product rule


`f'(x)=u'v+v'u`


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