Higher November 2018 Paper 4 Q14
14 \(y\) is inversely proportional to the square root of \(x\).
\(y\) is 40 when \(x\) is 9.
Find a formula linking \(x\) and \(y\). [3]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| \(y = \dfrac{120}{\sqrt{x}}\) oe | 3 | M1 for \(y = \dfrac{k}{\sqrt{x}}\) oe B1 for [\(k =\)] 120 | e.g. condone \(y = \dfrac{k}{\sqrt{9}}\) for M1 |