1. differentiate cos(3/x)
2. differentiate sin(4/x)
3. differentiate 3/{sin(3x+pi)}
4. differentiate pxsin(q/x)where p and q are constants.
5. differentiate xsin(a/x) where a is constant
6. differentiate sec^3(3x^2+1)
2. differentiate sin(4/x)
3. differentiate 3/{sin(3x+pi)}
4. differentiate pxsin(q/x)where p and q are constants.
5. differentiate xsin(a/x) where a is constant
6. differentiate sec^3(3x^2+1)