\magnification 1400 \parskip 10pt \parindent 0pt \hoffset -0.3truein \hsize 7truein \voffset -0.4truein \vsize 10truein \def\emph{} %%\def\S{\Sigma_{i=1}^n} \def\Sm{\Sigma_{i=1}^m} \def\S{\sum_{i=1}^n} \def\s{{\sigma}} \def\ep{\epsilon} \def\f{\vskip 10pt} \def\h{\hskip 10pt} \def\u{\vskip -8pt} \def\bh{\hfil \break} \def\N{{\bf N}} \def\S{\Sigma_{i=1}^n} \def\0{{\bf 0}} \def\Z{{\bf Z}} \def\R{{\bf R}} \def\C{{\bf C}} \def\x{{\bf x}} \def\a{{\bf a}} \def\y{{\bf y}} \def\e{{\bf e}} \def\i{{\bf i}} \def\j{{\bf j}} \def\k{{\bf k}} \def\p{{\bf p}} \def\f{\phi} \def\s{\sigma} \def\ep{\epsilon} \def\f{\vskip 10pt} \def\u{ \vskip -5pt } \def\h{\vskip -5pt \hskip 20pt} \def\grad{ \nabla } \def\tens{ \otimes } \def\l{\vskip 5pt \hrule \vskip -5pt} \l Let $\Lambda$ be an algebra over $\R$ The exterior algebra $\Lambda_n^*$ is the algebra with product $\wedge$ generated by $v_1, ..., v_n$ with unit such that $v_i \wedge v_j = - v_j \wedge v_i$ \l Let $V$ be a finite-dimensional vector space over $\R$. The dual of $V$ = $V^* = \{f: V \rightarrow \R ~|~ f$ linear $\}$ Note $V^*$ is a vector space. The elements of $V^*$ are called {\it covectors}. If $e_1, ..., e_n$ basis for $V$, then $w_1, ..., w_n$ basis for $V^*$ where $w_i: V \rightarrow \R$ where $w_i(e_j) = \delta_{ij} = \cases{1 & $i = j$ \cr 0 & $i \not= j$}$ Let $F_*: V \rightarrow W$ be a linear map between vector spaces \bh The dual map map is $F^*: W^* \rightarrow V^*$, $F(g) = g \circ F$. $F_*$ is injective implies $F^*$ injective $F_*$ is surjective implies $F^*$ surjective $(G_* \circ F_*)^* = F^* \circ G^*$. $d: V \rightarrow (V^*)^*$, $d(v) = h$ where $h: V^* \rightarrow R$, $h(f) = f(v)$. Thus $ (V^*)^*$ is naturally isomorphic to $V$. \l Defn: The dual of $T_pM= T_p^*M$ is the {\it cotangent space} to $M$ at $p$. If $ {\partial \over \partial x_1}, ..., {\partial \over \partial x_m}$ is a basis for $T_pM$, then the dual basis will be denoted $dx_1, ..., dx_m$. %%Defn: The cotangent bundle of M \end