Answer and explanation

Correct answer: A. or

  1. Step 1: Find the critical values by setting the quadratic expression to zero: or .
  2. Step 2: Consider the sign of the parabola : because the coefficient of is positive (), the parabola opens upwards.
  3. Step 3: The quadratic is strictly positive () outside the roots: or .
Answer
or .
Why not the others: is the solution to ; or swaps the signs of the roots from factoring .

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