#include <stdio.h> int main() { printf("Hello World"); return 0; }
行级模式:$\sum_{i=0}^N\int_{a}^{b}g(t, i)\text{d}t$
$\sum_{i=0}^N\int_{a}^{b}g(t, i)\text{d}t$
∑i=0N∫abg(t,i)dt
块级模式:$$\sum_{i=0}^N\int_{a}^{b}g(t, i)\text{d}t$$
$$\sum_{i=0}^N\int_{a}^{b}g(t, i)\text{d}t$$