4MA0 Higher January 2016 Paper 3 Q16
16 Solve the inequality \(5x^2 - 13 \lt 32\)
Show clear algebraic working.
(3)
| Scheme | Marks |
|---|---|
\(x^2 \lt 9\) or \(x^2 - 9 \lt 0\) or \(\dfrac{\pm\sqrt{-4 \times 5 \times -45}}{2 \times 5}\) | M1 |
\(\pm\sqrt{\text{"9"}}\) or ±3 or \((x + 3)(x - 3)\) or \(x \lt 3\) or \(x \gt -3\) | M1 |
| \(-3 \lt x \lt 3\) | A1 |
| (3) |
Notes
M1: Allow \(x^2 = 9\) or \(x^2 - 9 = 0\)