Higher June 2024 Paper 1 Q17
17
(a) Rationalise the denominator of \(\dfrac{1}{\sqrt{7}}\) (1)
(b) Simplify fully \(\sqrt{80} - \sqrt{5}\) (2)
| Answer | Mark | Mark scheme |
|---|---|---|
| \(\dfrac{\sqrt{7}}{7}\) | B1 | for \(\dfrac{\sqrt{7}}{7}\) or \(\dfrac{k\sqrt{7}}{7k}\) or \(\dfrac{\sqrt{7k^2}}{7k}\) where \(k\) is an integer not equal to 0 |
| Answer | Mark | Mark scheme |
|---|---|---|
| \(3\sqrt{5}\) | M1 | for writing \(\sqrt{80}\) as \(\sqrt{16 \times 5}\) or \(\sqrt{16} \times \sqrt{5}\) or \(4\sqrt{5}\) |
| A1 | for \(3\sqrt{5}\) or \(\sqrt{45}\) |