Integrate the function $345$ from 0 to $\infty $

Evaluate the integral

$\int_0^{\infty}\left(\frac{1}{x^2}\right)dx$

Evaluate the integral

$\int_0^1\left(\frac{3}{x^5}\right)dx$

Evaluate the integral

$\int_1^{\infty}\left(\frac{1}{x^2}\right)dx$

Evaluate the integral

$\int_1^{\infty}\left(\frac{ln\left(x\right)}{x}\right)dx$

Evaluate the integral

$\int_1^{\infty}\left(\frac{lnx}{x}\right)dx$

Evaluate the integral

$\int_1^{\infty}\left(\frac{1}{x^3}\right)dx$

Evaluate the integral

$\int_{-\infty}^0\left(\frac{1}{\sqrt{3-x}}\right)dx$