Both 9 and 10 please

9. [C/ 6 MARKS, A/6 MARKS] Differentiate then simply each of the following: a) f (x) =- x - 1 b) f (x ) = x- + 1 c) S ( x) = 5 sin x d) f (x) = = sin x COS X e) f (x) = Vx f) S ( x ) =- In x In x sin x 10. [A/ 5 MARKS] Find the intervals of concavity for the following functions a) f(x) = x2ex b) f(x) = x In x