Differentiate each of the following expressions.

1. $\frac { d } { d z }$$[ 2 z ^ { 2 } \operatorname { sec } ( z ^ { 3 } - 2 ) ]$ 

2. $\frac { d } { d t }$$[ \operatorname { sin } ( \operatorname { tan } ^ { 2 } ( 3 t - 5 ) ) ]$ 

   Answer (b):

   $6\cos(\tan^2(3t−5))\tan(3t−5)\sec^2(3t−5)$

3. $\frac { d } { d x }$$[ x \cdot 2 ^ { x } \operatorname { cos } ( x ) ]$