$$\newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} }$$
$$\newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}}$$
Thumbnail: The graph shows the function $$\displaystyle y=sinx$$ and the Maclaurin polynomials $$\displaystyle p_1,p_3$$ and $$\displaystyle p_5$$. Image used with permission (CC BY-SA 3.0; OpenStax).