(测试)LaTeX公式

[a^2+b^2=c^2 ]

[F(omega)=mathcal{F}[f(t)]=int_{-infty}^infty f(t)e^{-iwt}\,dt ]

[sum_{i=0}^n C_i^n =2^n ]

[O(Nlog N) ]

[O (sqrt{N^3}) ]

[min_{1le i le N\1le j <i}{ ext{somthing}} ]

[f'(x)=lim_{Delta x ightarrow 0} frac{f(x+Delta x)-f(x)}{Delta x} ]