Edexcel FP1 2013 June — Question 1 5 marks

Exam BoardEdexcel
ModuleFP1 (Further Pure Mathematics 1)
Year2013
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMatrices
TypeDeterminant calculation
DifficultyModerate -0.8 This is a straightforward Further Maths question requiring basic determinant calculation (2×2 matrix formula) and understanding that zero area means zero determinant. Both parts are direct application of standard techniques with minimal problem-solving, making it easier than average even for Further Maths.
Spec4.03h Determinant 2x2: calculation4.03i Determinant: area scale factor and orientation

  1. \(\mathbf { M } = \left( \begin{array} { c c } a & 1 \\ 1 & 2 - a \end{array} \right)\), where \(a\) is a constant.
    1. Find det M in terms of \(a\).
      (2)
    A triangle \(T\) is transformed to \(T ^ { \prime }\) by the matrix M .
    Given that the area of \(T ^ { \prime }\) is 0 ,
  2. find the value of \(a\).
    (3)

Question 1:
Part (a)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(\det \mathbf{M} = a(2-a)-1\)M1A1 M1 for "\(ad-bc\)"
(2)
Part (b)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(\det \mathbf{M} = 0\)M1 First M for setting \(\det \mathbf{M} = 0\)
\(a^2 - 2a + 1 = 0\)M1 Second M for attempt to solve their 3 term quadratic
\((a-1)^2 = 0\) Method mark for solving 3 term quadratic: factorisation, formula, or completing the square
\(a = 1\)A1
(3) [5]
# Question 1:

## Part (a)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $\det \mathbf{M} = a(2-a)-1$ | M1A1 | M1 for "$ad-bc$" |
| | **(2)** | |

## Part (b)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $\det \mathbf{M} = 0$ | M1 | First M for setting $\det \mathbf{M} = 0$ |
| $a^2 - 2a + 1 = 0$ | M1 | Second M for attempt to solve their 3 term quadratic |
| $(a-1)^2 = 0$ | | Method mark for solving 3 term quadratic: factorisation, formula, or completing the square |
| $a = 1$ | A1 | |
| | **(3) [5]** | |

---
\begin{enumerate}
  \item $\mathbf { M } = \left( \begin{array} { c c } a & 1 \\ 1 & 2 - a \end{array} \right)$, where $a$ is a constant.\\
(a) Find det M in terms of $a$.\\
(2)
\end{enumerate}

A triangle $T$ is transformed to $T ^ { \prime }$ by the matrix M .\\
Given that the area of $T ^ { \prime }$ is 0 ,\\
(b) find the value of $a$.\\
(3)\\

\hfill \mbox{\textit{Edexcel FP1 2013 Q1 [5]}}