TeXコマンド	MathJaxの出力
\rightarrow	$\rightarrow$
\Rightarrow	$\Rightarrow$
\leftarrow	$\leftarrow$
\Leftarrow	$\Leftarrow$
\leftrightarrow	$\leftrightarrow$
\Leftrightarrow	$\Leftrightarrow$
\mapsto	$\mapsto$
\longmapsto	$\longmapsto$
\hookleftarrow	$\hookleftarrow$
\hookrightarrow	$\hookrightarrow$
\leftharpoonup	$\leftharpoonup$
\rightharpoonup	$\rightharpoonup$
\leftharpoondown	$\leftharpoondown$
\rightharpoondown	$\rightharpoondown$
\rightleftharpoons	$\rightleftharpoons$
\nearrow	$\nearrow$
\searrow	$\searrow$
\swarrow	$\swarrow$
\nwarrow	$\nwarrow$
\dashrightarrow	$\dashrightarrow$
\dashleftarrow	$\dashleftarrow$
\longleftarrow	$\longleftarrow$
\longrightarrow	$\longrightarrow$
\Longrightarrow	$\Longrightarrow$
\longleftrightarrow	$\longleftrightarrow$
\Longleftrightarrow	$\Longleftrightarrow$
\leftrightsquigarrow	$\leftrightsquigarrow$
\rightsquigarrow	$\rightsquigarrow$
\Updownarrow	$\Updownarrow$
\downharpoonleft	$\downharpoonleft$
\downharpoonright	$\downharpoonright$
\upharpoonleft	$\upharpoonleft$
\upharpoonright	$\upharpoonright$
\rightleftarrows	$\rightleftarrows$
\leftrightarrows	$\leftrightarrows$
\leftleftarrows	$\leftleftarrows$
\rightrightarrows	$\rightrightarrows$
\Lleftarrow	$\Lleftarrow$
\Rrightarrow	$\Rrightarrow$
\longmapsto	$\longmapsto$
\hookleftarrow	$\hookleftarrow$
\hookrightarrow	$\hookrightarrow$
\nrightarrow	$\nrightarrow$
\nleftarrow	$\nleftarrow$
\nleftrightarrow	$\nleftrightarrow$
\rightsquigarrow	$\rightsquigarrow$
\leftrightharpoons	$\leftrightharpoons$
\rightleftharpoons	$\rightleftharpoons$
\leadsto	$\leadsto$
\Rsh	$\Rsh$
\Lsh	$\Lsh$
\upuparrows	$\upuparrows$
\downdownarrows	$\downdownarrows$
\upharpoonleft	$\upharpoonleft$
\upharpoonright	$\upharpoonright$
\downharpoonleft	$\downharpoonleft$
\downharpoonright	$\downharpoonright$
\dashrightarrow	$\dashrightarrow$
\dashleftarrow	$\dashleftarrow$

LaTexで不等式・不等号を書く方法と便利なパッケージ