我想将数学文档转换为 pdf，但是出现了缺少 $ 的错误。
这是我的代码：
\documentclass{article}
\begin{document}
1. All prime numbers are odd
Universal Statement:
For all x \in \mathbb{N} such that for any a,b \in \mathbb{N}
x = ab where a or b must be equal to 1 and for any k \in \mathbb{N}, x = 2k + 1
Counterexample will comprise of:
A counterexample will be an x \in \mathbb{N} such that there exists a k \in \mathbb{N}
such that x = 2k
Counterexample:
2
6. For all real numbers x, we have x^2-2x+2 > 1
Universal Statement:
For all x \in \mathbb{R}, we have x^2-2x+2 > 1
Counterexample will comprise of:
A counterexample will be an x such that x^2-2x+2 < 1
Counterexample:
1
14. For all functions f : \mathbb{R} \rightarrow \mathbb{R}, if f is not increasing,
then it must be decreasing.
Universal Statement:
For all functions f : \mathbb{R} \rightarrow \mathbb{R} for all x_1, x_2 if
x_1 < x_2 and f(x_1) \ngeq f(x_2) then f(x_1) \leq f(x_2)
Counterexample will comprise of:
A counterexample will be a function f such that for all x_1, x_2 if x_1 < x_2 and
f(x_1) \ngeq f(x_2) then f(x_1) \nleq f(x_2)
Counterexample:
None, the statement is true
\end{document}
答案1
有什么疑问？你绝不在此文档中使用 $。例如，x \in \mathbb{N}您应该写成 而$x \in \mathbb{N}$不是 ，并且x^2-2x+2 > 1您应该写成而不是$x^2-2x+2 > 1$。