OCR MEI Further Pure Core AS Specimen — Question 5 7 marks

Exam BoardOCR MEI
ModuleFurther Pure Core AS (Further Pure Core AS)
SessionSpecimen
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicRoots of polynomials
TypeRoots with special relationships
DifficultyChallenging +1.2 This is a Further Maths AS question requiring systematic use of Vieta's formulas and algebraic manipulation with related roots. While it involves multiple steps and careful algebra, the approach is methodical: use sum of roots to find α, then verify and find p. The relationship between roots provides strong structure, making it more straightforward than it initially appears, though still above average difficulty due to the algebraic complexity and being Further Maths content.
Spec4.05a Roots and coefficients: symmetric functions

The cubic equation \(x^3 - 4x^2 + px + q = 0\) has roots \(\alpha\), \(\frac{2}{\alpha}\) and \(\alpha + \frac{2}{\alpha}\). Find
  • the values of the roots of the equation,
  • the value of \(p\).
[7]

Question 5:
AnswerMarks
52 2
(cid:68)(cid:14) (cid:14)(cid:68)(cid:14) (cid:32)4
(cid:68) (cid:68)
(cid:68)2 (cid:16)2(cid:68)(cid:14)2(cid:32)0
(cid:68)(cid:32)1(cid:114)i
Roots are 1(cid:14)i,1(cid:16)i,2
p(cid:32)(1(cid:14)i)(1(cid:16)i)(cid:14)2(1(cid:14)i)(cid:14)2(1(cid:16)i)
(cid:32)2(cid:14)2(cid:14)2i(cid:14)2(cid:16)2i
AnswerMarks
= 4M1
M1
A1
A1
M1
A1
A1
AnswerMarks
[7]1.1a
3.1a
1.1
3.2a
3.1a
1.1
AnswerMarks
1.1Attempt to use sum of roots
N
Interpret solution of quadratic
Eto get all three roots of cubic
Some correct simplification
Question 5:
5 | 2 2
(cid:68)(cid:14) (cid:14)(cid:68)(cid:14) (cid:32)4
(cid:68) (cid:68)
(cid:68)2 (cid:16)2(cid:68)(cid:14)2(cid:32)0
(cid:68)(cid:32)1(cid:114)i
Roots are 1(cid:14)i,1(cid:16)i,2
p(cid:32)(1(cid:14)i)(1(cid:16)i)(cid:14)2(1(cid:14)i)(cid:14)2(1(cid:16)i)
(cid:32)2(cid:14)2(cid:14)2i(cid:14)2(cid:16)2i
= 4 | M1
M1
A1
A1
M1
A1
A1
[7] | 1.1a
3.1a
1.1
3.2a
3.1a
1.1
1.1 | Attempt to use sum of roots
N
Interpret solution of quadratic
Eto get all three roots of cubic
Some correct simplification
The cubic equation $x^3 - 4x^2 + px + q = 0$ has roots $\alpha$, $\frac{2}{\alpha}$ and $\alpha + \frac{2}{\alpha}$.

Find
\begin{itemize}
\item the values of the roots of the equation,
\item the value of $p$.
\end{itemize}
[7]

\hfill \mbox{\textit{OCR MEI Further Pure Core AS  Q5 [7]}}