CAIE P1 2020 Specimen — Question 1 3 marks

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2020
SessionSpecimen
Marks3
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicDifferentiation from First Principles
TypeNumerical gradient deduction
DifficultyEasy -1.2 This is a straightforward application of reading gradient values from a table to estimate the derivative at a point, requiring only basic understanding that gradient of a chord approximates the derivative. It's simpler than average A-level questions as it involves minimal calculation and is primarily about interpreting given numerical data rather than performing differentiation.
Spec1.07a Derivative as gradient: of tangent to curve1.07b Gradient as rate of change: dy/dx notation

1 The following points $$A ( 0,1 ) , \quad B ( 1,6 ) , \quad C ( 1.5,7.75 ) , \quad D ( 1.9,8.79 ) \quad \text { and } \quad E ( 2,9 )$$ lie on the curve \(y = \mathrm { f } ( x )\). The table below shows the gradients of the chords \(A E\) and \(B E\).
Chord\(A E\)\(B E\)\(C E\)\(D E\)
Gradient of
chord
43
  1. Complete the table to show the gradients of \(C E\) and \(D E\).
  2. State what the values in the table indicate about the value of \(\mathrm { f } ^ { \prime } ( 2 )\).

Question 1(a):
AnswerMarks Guidance
AnswerMarks Guidance
Gradient of \(CE = 2.5\)1 B1
Gradient of \(DE = 2.1\)1 B1
\(f'(2) = 2\)2 B1 Accept reasonable conclusion following their gradient
Question 1(b):
AnswerMarks Guidance
AnswerMarks Guidance
\(f'(2) = 2\)1 B1 Accept reasonable conclusion following their gradient
## Question 1(a):
| Answer | Marks | Guidance |
|--------|-------|----------|
| Gradient of $CE = 2.5$ | 1 B1 | |
| Gradient of $DE = 2.1$ | 1 B1 | |
| $f'(2) = 2$ | 2 B1 | Accept reasonable conclusion following their gradient |

## Question 1(b):
| Answer | Marks | Guidance |
|--------|-------|----------|
| $f'(2) = 2$ | 1 B1 | Accept reasonable conclusion following their gradient |
1 The following points

$$A ( 0,1 ) , \quad B ( 1,6 ) , \quad C ( 1.5,7.75 ) , \quad D ( 1.9,8.79 ) \quad \text { and } \quad E ( 2,9 )$$

lie on the curve $y = \mathrm { f } ( x )$. The table below shows the gradients of the chords $A E$ and $B E$.

\begin{center}
\begin{tabular}{ | c | c | c | c | c | }
\hline
Chord & $A E$ & $B E$ & $C E$ & $D E$ \\
\hline
\begin{tabular}{ c }
Gradient of \\
chord \\
\end{tabular} & 4 & 3 &  &  \\
\hline
\end{tabular}
\end{center}

(a) Complete the table to show the gradients of $C E$ and $D E$.\\
(b) State what the values in the table indicate about the value of $\mathrm { f } ^ { \prime } ( 2 )$.\\

\hfill \mbox{\textit{CAIE P1 2020 Q1 [3]}}