| Exam Board | OCR MEI |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Year | 2013 |
| Session | January |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Indices and Surds |
| Type | Evaluate numerical powers |
| Difficulty | Easy -1.8 This is a straightforward recall question testing basic index laws with no problem-solving required. Both parts involve direct application of negative and fractional indices to simple numbers, making it easier than the calibration example at -1.5 which had similar complexity but slightly more parts. |
| Spec | 1.02a Indices: laws of indices for rational exponents |
| Answer | Marks | Guidance |
|---|---|---|
| \(x = 3\) | B1 | cao |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| \(\frac{9}{25}\) or \(0.36\) isw | M1 | For numerator or denominator correct, or for squaring correctly, or for inverting correctly. e.g. \(\frac{1}{\frac{25}{9}}\) or \(\left(\frac{25}{9}\right)^{-1}\) or \(\frac{25}{9}\) or \(\left(\frac{3}{5}\right)^2\) or \(\frac{3}{5}\). M0 for just \(\frac{1}{\left(\frac{5}{3}\right)^2}\) |
| A1 | ||
| [2] |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| \(27\) | M1 | For \(81^{\frac{1}{4}} = 3\) soi. e.g. M1 for \(3^3\). M0 for \(81^3 = 531441\) (true but not helpful) |
| A1 | ||
| [2] |
**Question 1:**
$x = 3$ | B1 | cao
etc.
# Mark Scheme - 4751 January 2013
---
## Question 1(i):
| Answer | Marks | Guidance |
|--------|-------|----------|
| $\frac{9}{25}$ or $0.36$ isw | M1 | For numerator or denominator correct, or for squaring correctly, or for inverting correctly. e.g. $\frac{1}{\frac{25}{9}}$ or $\left(\frac{25}{9}\right)^{-1}$ or $\frac{25}{9}$ or $\left(\frac{3}{5}\right)^2$ or $\frac{3}{5}$. M0 for just $\frac{1}{\left(\frac{5}{3}\right)^2}$ |
| | A1 | |
| **[2]** | | |
---
## Question 1(ii):
| Answer | Marks | Guidance |
|--------|-------|----------|
| $27$ | M1 | For $81^{\frac{1}{4}} = 3$ soi. e.g. M1 for $3^3$. M0 for $81^3 = 531441$ (true but not helpful) |
| | A1 | |
| **[2]** | | |
---1 Find the value of each of the following.\\
(i) $\left( \frac { 5 } { 3 } \right) ^ { - 2 }$\\
(ii) $81 ^ { \frac { 3 } { 4 } }$
\hfill \mbox{\textit{OCR MEI C1 2013 Q1 [4]}}