Posted by **I'm stumped** on Friday, June 19, 2009 at 8:25am.

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)