Let the given function be,
f( x )=( a x 2 +sinx )( p+qcosx )
Differentiate the function with respect to x,
f ′ ( x )=( a x 2 +sinx ) d dx ( p+qcosx )+( p+qcosx ) d dx ( a x 2 +sinx ) =( a x 2 +sinx )[ q( −sinx ) ]+( p+qcosx )( a( 2x )+cosx ) =( a x 2 +sinx )( −qsinx )+( p+qcosx )( 2ax+cosx )
Therefore, the derivative of the given function is ( a x 2 +sinx )( −qsinx )+( p+qcosx )( 2ax+cosx ).
Find the 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): (ax2 + sin x) (p + q cos x)