Rational equations and inequalities

9000025807

Level: 
C
In the following list identify a true statement on the function \(f\). \[ f(x) = \frac{-2(3x + 1)} {(2x + 3)(2 - x)} \]
\(f(x) > 0 \iff x\in \left (-\frac{3} {2};-\frac{1} {3}\right )\cup (2;\infty )\)
\(f(x) > 0 \iff x\in \left (-\infty ;-\frac{3} {2}\right )\cup \left (-\frac{1} {3};2\right )\)
\(f(x) > 0 \iff x\in \left (-\frac{3} {2};2\right )\)
\(f(x) > 0 \iff x\in \left (-\infty ;-\frac{3} {2}\right )\cup (2;\infty )\)

9000024105

Level: 
A
Identify the optimal first step to solve the following equation. The operation is intended to be used on both sides of the equation. \[ \frac{4 + x} {x + 1} = \frac{x - 3} {x + 2} \]
multiply by \((x + 2)\cdot (x + 1)\), assuming \(x\neq - 2\) and \(x\neq - 1\)
multiply by \((4 + x)\cdot (x - 3)\), assuming \(x\neq - 4\) and \(x\neq 3\)
multiply by \((4 + x)\cdot (x + 1)\), assuming \(x\neq - 4\) and \(x\neq - 1\)
multiply by \((x - 3)\cdot (x + 2)\), assuming \(x\neq 3\) and \(x\neq - 2\)
multiply by \((x - 3)\), assuming \(x\neq 3\)
multiply by \((4 + x)\), assuming \(x\neq - 4\)