2 (i) Use the trapezium rule with 3 intervals to estimate the value of

$$\int _ { \frac { 1 } { 6 } \pi } ^ { \frac { 2 } { 3 } \pi } \operatorname { cosec } x d x$$

giving your answer correct to 2 decimal places.\\
(ii) Using a sketch of the graph of $y = \operatorname { cosec } x$, explain whether the trapezium rule gives an overestimate or an underestimate of the true value of the integral in part (i).

\hfill \mbox{\textit{CAIE P3 2014 Q2}}