| Exam Board | OCR MEI |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Year | 2016 |
| Session | June |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Completing the square and sketching |
| Type | Sketch quadratic curve |
| Difficulty | Easy -1.3 This is a straightforward question requiring basic algebraic manipulation to solve a simple quadratic equation and sketching a parabola in completed square form. The vertex and intercepts are immediately readable from the equation with minimal calculation, making this easier than average A-level content. |
| Spec | 1.02f Solve quadratic equations: including in a function of unknown1.02m Graphs of functions: difference between plotting and sketching |
| Answer | Marks | Guidance |
|---|---|---|
| \([x=]5,\ [x=]-1\) www | M1 for \(x-2=\pm3\) or for \((x-5)(x+1)[=0]\) | 0 for just \(x=5\) or \(x-2=3\) [2] |
| Answer | Marks | Guidance |
|---|---|---|
| parabola shape curve correct way up | 1 | must extend beyond \(x\)-axis; condone 'U' shape or very slight curving; must not be ruled; condone fairly straight with clear attempt at curve at minimum |
| intersecting \(x\)-axis at 5 and \(-1\) or ft from (i) and \(y\)-axis at \(-5\) | 1 | |
| turning point \((2,-9)\) | 1 | seen on graph or identified as tp elsewhere; may be implied by 2 and \(-9\) marked on axes [3] |
# Question 7:
## Part (i)
$[x=]5,\ [x=]-1$ www | M1 for $x-2=\pm3$ or for $(x-5)(x+1)[=0]$ | 0 for just $x=5$ or $x-2=3$ [2]
## Part (ii)
parabola shape curve correct way up | 1 | must extend beyond $x$-axis; condone 'U' shape or very slight curving; must not be ruled; condone fairly straight with clear attempt at curve at minimum
intersecting $x$-axis at 5 and $-1$ or ft from (i) and $y$-axis at $-5$ | 1 |
turning point $(2,-9)$ | 1 | seen on graph or identified as tp elsewhere; may be implied by 2 and $-9$ marked on axes [3]
---7 (i) Solve the equation $( x - 2 ) ^ { 2 } = 9$.\\
(ii) Sketch the curve $y = ( x - 2 ) ^ { 2 } - 9$, showing the coordinates of its intersections with the axes and its turning point.
\hfill \mbox{\textit{OCR MEI C1 2016 Q7 [5]}}