Standard +0.8 This requires applying the Maclaurin series formula to a shifted trigonometric function, involving multiple derivatives of tan(x + π/4) evaluated at x=0. Students must use the chain rule repeatedly and handle the algebra of tan derivatives, which is more demanding than standard Maclaurin series of simple functions but follows a systematic procedure.
1 Find the Maclaurin's series for $\tan \left( x + \frac { 1 } { 4 } \pi \right)$ up to and including the term in $x ^ { 2 }$.\\
\hfill \mbox{\textit{CAIE Further Paper 2 2020 Q1 [5]}}