CAIE P1 2010 November — Question 3 4 marks

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2010
SessionNovember
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicDifferentiating Transcendental Functions
TypeApplied rate of change
DifficultyEasy -1.2 This is a straightforward application of the chain rule to differentiate a simple composite function (square root of a linear expression), followed by direct substitution. It requires only basic differentiation technique with no problem-solving or conceptual insight, making it easier than average for A-level.
Spec1.07b Gradient as rate of change: dy/dx notation1.07i Differentiate x^n: for rational n and sums

3 The length, \(x\) metres, of a Green Anaconda snake which is \(t\) years old is given approximately by the formula $$x = 0.7 \sqrt { } ( 2 t - 1 ) ,$$ where \(1 \leqslant t \leqslant 10\). Using this formula, find
  1. \(\frac { \mathrm { d } x } { \mathrm {~d} t }\),
  2. the rate of growth of a Green Anaconda snake which is 5 years old.

Question 3:
Part (i)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\((k(2t-1)^{-1/2}\)M1 \(k \neq 1\)
\(0.7(2t-1)^{-1/2}\)A1 oe
Part (ii)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Sub \(t=5\) into their derivativeM1
\(0.23(3)\)A1 Ignore units
## Question 3:

**Part (i)**

| Answer/Working | Marks | Guidance |
|---|---|---|
| $(k(2t-1)^{-1/2}$ | M1 | $k \neq 1$ |
| $0.7(2t-1)^{-1/2}$ | A1 | oe |

**Part (ii)**

| Answer/Working | Marks | Guidance |
|---|---|---|
| Sub $t=5$ into their derivative | M1 | |
| $0.23(3)$ | A1 | Ignore units |

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3 The length, $x$ metres, of a Green Anaconda snake which is $t$ years old is given approximately by the formula

$$x = 0.7 \sqrt { } ( 2 t - 1 ) ,$$

where $1 \leqslant t \leqslant 10$. Using this formula, find\\
(i) $\frac { \mathrm { d } x } { \mathrm {~d} t }$,\\
(ii) the rate of growth of a Green Anaconda snake which is 5 years old.

\hfill \mbox{\textit{CAIE P1 2010 Q3 [4]}}