The parametric form of a curve is $$x=\frac{t^3}{t^2-1} y=\frac{t}{t^2-1}$$, then $$\int \frac{d x}{x-3 y}=$$

If

$$\begin{aligned} \frac{2 x^4-x^3+3 x^2-x+4}{x^2-3 x+2} =f(x)+\frac{A}{x-1}+\frac{B}{x-2}\end{aligned}$$, then

If $$f^{\prime}(x)=x+\frac{1}{x}$$, then $$f(x)$$ is equal to

If $$f(x)=\frac{1}{\left(\cos ^2 x\right) \sqrt{1+\tan x}}$$, then its antiderivative $$F(x)=$$ ........, given, $$F(0)=4$$