Rational functions

1003124601

Level: 
B
Let \( f(x)=\frac{2x}{x^2-1} \). Find the true statement.
\( \forall x\in(-\infty;-1)\cup(0;1)\colon f(x) < 0 \).
The domain of \( f \) is \( (-\infty;1)\cup(1;\infty) \).
\( \forall x\in(-1;1)\colon f(x) \leq 0 \).
The domain of \( f \) is \( (-\infty;-1)\cup(-1;0)\cup(0;1)\cup(1;\infty) \).

1103030902

Level: 
B
A part of the graph of the function \( f(x)=\frac4x \) is shown in the picture. Identify which of the following statements is true.
The function \( g \) defined by \( g(x)=\left|f(x)\right| \) is bounded below.
The function \( f \) is bounded below.
The function $h$ defined by \( h(x)=-f(x) \) is bounded below.
The function $m$ defined by \( m(x)=f(x)+4 \) is bounded below.