我不需要 \right，但它给出了错误

Question

这是我的文字

没有右括号，我也不需要

但我收到这个错误

如何修复？

Answer 1

\documentclass{article}
\usepackage{amsmath}

\begin{document}
Courtesy of mathpix we can get with 60\% confidence several alternatives ...
Note it uses the correct $\ right.$ construction
By nature of its one line approach it uses $\backslash\backslash$ however you can remove any surplus by editing them out.

\vspace{1em} 

\[ % per comment by egreg
\left\{%
\begin{array}{l}
{y_{i}-\left\langle\mathbf{w}, \mathbf{x}_{\mathbf{i}}\right\rangle- b \leq \epsilon+\zeta_{i}^{*}}\cr % manually replace \linebreak with a carriage return
{\left\langle\mathbf{w}, \mathbf{x}_{\mathbf{i}}\right\rangle+ b-y_{i} \leq \epsilon+\zeta_{i}}
\end{array}
\right.% suppress right bracket
\]

\begin{equation}
\left\{\begin{array}{l}{y_{i}-\left\langle\mathbf{w}, \mathbf{x}_{\mathbf{i}}\right\rangle- b \leq \epsilon+\zeta_{i}^{*}} \\ {\left\langle\mathbf{w}, \mathbf{x}_{\mathbf{i}}\right\rangle+ b-y_{i} \leq \epsilon+\zeta_{i}}\end{array}\right.
\end{equation}

\end{document}

Answer 2

最好使用cases环境amsmath，用法如下：

\usepackage{amsmath}

\begin{document}

\[
\begin{cases}
.... & ...\\
.... &
\end{cases}
\]

如果您使用这个，那么支撑和对齐将会变得更好......

Answer 3

我认为这两个公式应该在符号处对齐≤，左边{只是为了分组，这些都不是情况。aligned可以在这里完美使用。

\documentclass{article}
\usepackage{amsmath}
\begin{document}

\[
\left\{\begin{aligned}
y_i - \langle\mathbf{w}, \mathbf{x_i}\rangle - b &\leq \epsilon+\zeta_i^* \\ 
\langle\mathbf{w}, \mathbf{x_i}\rangle + b - y_i &\leq \epsilon+\zeta_i
\end{aligned}\right.
\]

\end{document}