If y = x\(^2\) – x – 12, find the range of values of x for which y \( \geq \) 0
- x < -3 0r x > 4
-
x \( \leq \) -3 or x \( \geq \) 4
- -3 < x \( \geq \) 4
- -3 \( \leq \) x \( \leq \) 4
The correct answer is: B
Explanation
y = x\(^2\) - x - 12
= (x - 4)(x + 3)
∴ x = 4 or x = -3
Checking the cases for y \( \geq \) 0
We check values on the range x - 4 \(\geq\) 0; x + 3 \(\leq\) 0; x - 4 \(\leq\) 0 and x + 3 \(\geq\) 0 for the range which satisfies the inequality x\(^2\) - x - 12 \(\geq\) 0.
We find that the inequality is satisfied on the range x \(\leq\) -3 and x \(\geq\) 4.