The function $f(x)=\frac{x}{3}+\frac{3}{x}$ decreases in the interval

Let $f(x)=e^x-x$ and $g(x)=x^2-x, \forall x \in R$. Then the set of all $x \in R$,where the function $h(x)=(fog)(x)$ is increasing is

Let $f(x) = \int e^x (x - 1)(x - 2) dx$. In which interval is $f$ a decreasing function?

Observe the following statements:
$A: f(x) = 2x^3 - 9x^2 + 12x - 3$ is increasing outside the interval $(1, 2)$.
$R: f^{\prime}(x) < 0$ for $x \in (1, 2)$.
Then,which of the following is true?

In which interval is the function $f(x) = \frac{x}{\ln x}$ increasing?

The function $\frac{a\sin x + b\cos x}{c\sin x + d\cos x}$ is decreasing,if