Edexcel C1 2010 June — Question 11 9 marks

Exam BoardEdexcel
ModuleC1 (Core Mathematics 1)
Year2010
SessionJune
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicIndefinite & Definite Integrals
TypeCurve properties and tangent/normal
DifficultyModerate -0.3 This is a straightforward C1 integration question requiring standard techniques: integrating powers of x (including x^{-1/2}), finding the constant using a given point, then finding a tangent equation. All steps are routine with no problem-solving insight needed, making it slightly easier than average but not trivial due to the multiple parts and algebraic manipulation required.
Spec1.07i Differentiate x^n: for rational n and sums1.07m Tangents and normals: gradient and equations1.08b Integrate x^n: where n != -1 and sums

  1. The curve \(C\) has equation \(y = \mathrm { f } ( x ) , \quad x > 0\), where
$$\frac { \mathrm { d } y } { \mathrm {~d} x } = 3 x - \frac { 5 } { \sqrt { } x } - 2$$ Given that the point \(P ( 4,5 )\) lies on \(C\), find
  1. \(\mathrm { f } ( x )\),
  2. an equation of the tangent to \(C\) at the point \(P\), giving your answer in the form \(a x + b y + c = 0\), where \(a , b\) and \(c\) are integers.

Question 11:
Part (a):
AnswerMarks Guidance
AnswerMark Guidance
\((y=)\frac{3x^2}{2} - \frac{5x^{\frac{1}{2}}}{\frac{1}{2}} - 2x\) \((+c)\)M1A1A1 Attempt to integrate \(x^n \to x^{n+1}\); 1st A1 at least 2 correct terms; 2nd A1 all 3 terms correct (condone missing \(+c\))
\(f(4) = 5 \Rightarrow 5 = \frac{3}{2} \times 16 - 10 \times 2 - 8 + c\)M1 Using point \((4,5)\) to form linear equation for \(c\); must use \(x=4\), \(y=5\) and function must have "changed"
\(c = 9\)A1
\(\left[f(x) = \frac{3}{2}x^2 - 10x^{\frac{1}{2}} - 2x + 9\right]\) Final expression not required
Part (b):
AnswerMarks Guidance
AnswerMark Guidance
\(m = 3 \times 4 - \frac{5}{2} - 2 = 7.5\) or \(\frac{15}{2}\)M1 Attempt to evaluate \(f'(4)\); must have at least \(3 \times 4\) or \(-\frac{5}{2}\) and clearly using \(f'(x)\) with \(x = 4\)
\(y - 5 = \frac{15}{2}(x-4)\)M1A1 Using value of \(m\) to form equation through \((4,5)\); 1st A1 for any correct expression for line
\(2y - 15x + 50 = 0\) (o.e.)A1 Any correct equation with integer coefficients; "=" required e.g. \(2y = 15x - 50\) acceptable
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## Question 11:

### Part (a):
| Answer | Mark | Guidance |
|--------|------|----------|
| $(y=)\frac{3x^2}{2} - \frac{5x^{\frac{1}{2}}}{\frac{1}{2}} - 2x$ $(+c)$ | M1A1A1 | Attempt to integrate $x^n \to x^{n+1}$; 1st A1 at least 2 correct terms; 2nd A1 all 3 terms correct (condone missing $+c$) |
| $f(4) = 5 \Rightarrow 5 = \frac{3}{2} \times 16 - 10 \times 2 - 8 + c$ | M1 | Using point $(4,5)$ to form linear equation for $c$; must use $x=4$, $y=5$ and function must have "changed" |
| $c = 9$ | A1 | |
| $\left[f(x) = \frac{3}{2}x^2 - 10x^{\frac{1}{2}} - 2x + 9\right]$ | | Final expression not required |

### Part (b):
| Answer | Mark | Guidance |
|--------|------|----------|
| $m = 3 \times 4 - \frac{5}{2} - 2 = 7.5$ or $\frac{15}{2}$ | M1 | Attempt to evaluate $f'(4)$; must have at least $3 \times 4$ or $-\frac{5}{2}$ and clearly using $f'(x)$ with $x = 4$ |
| $y - 5 = \frac{15}{2}(x-4)$ | M1A1 | Using value of $m$ to form equation through $(4,5)$; 1st A1 for any correct expression for line |
| $2y - 15x + 50 = 0$ (o.e.) | A1 | Any correct equation with integer coefficients; "=" required e.g. $2y = 15x - 50$ acceptable |

The images you've shared appear to be essentially blank pages — one is completely empty, and the other contains only publisher/contact information for Edexcel Publications (address, phone, fax, email, order code UA023696 Summer 2010, and company registration details).

There is **no mark scheme content** visible in these images. No questions, answers, mark allocations, or guidance notes are present.

Could you share the actual mark scheme pages? They may have been missed in the upload.
\begin{enumerate}
  \item The curve $C$ has equation $y = \mathrm { f } ( x ) , \quad x > 0$, where
\end{enumerate}

$$\frac { \mathrm { d } y } { \mathrm {~d} x } = 3 x - \frac { 5 } { \sqrt { } x } - 2$$

Given that the point $P ( 4,5 )$ lies on $C$, find\\
(a) $\mathrm { f } ( x )$,\\
(b) an equation of the tangent to $C$ at the point $P$, giving your answer in the form $a x + b y + c = 0$, where $a , b$ and $c$ are integers.

\hfill \mbox{\textit{Edexcel C1 2010 Q11 [9]}}