2. The function $g$ is defined for $x > 0$ with $g ( 1 ) = 2 , g ^ { \prime } ( x ) = \sin \left( x + \frac { 1 } { x } \right)$, and $g ^ { \prime \prime } ( x ) = \left( 1 - \frac { 1 } { x ^ { 2 } } \right) \cos \left( x + \frac { 1 } { x } \right)$.
(a) Find all values of $x$ in the interval $0.12 \leq x \leq 1$ at which the graph of $g$ has a horizontal tangent line.
(b) On what subintervals of $( 0.12,1 )$, if any, is the graph of $g$ concave down? Justify your answer.
(c) Write an equation for the line tangent to the graph of $g$ at $x = 0.3$.
(d) Does the line tangent to the graph of $g$ at $x = 0.3$ lie above or below the graph of $g$ for $0.3 < x < 1$ ? Why?
| $t$ | 0 | 2 | 4 | 6 | 8 | 10 | 12 |
| $P ( t )$ | 0 | 46 | 53 | 57 | 60 | 62 | 63 |
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