OCR MEI C2 — Question 2 11 marks

Exam BoardOCR MEI
ModuleC2 (Core Mathematics 2)
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTangents, normals and gradients
TypeNormal meets curve/axis — further geometry
DifficultyStandard +0.3 This is a standard C2 calculus question combining differentiation (finding normal), coordinate geometry, and definite integration for area. Part (i) involves routine differentiation, finding gradient of normal, and line equation - all textbook techniques. Part (ii) requires setting up and evaluating a definite integral with some care about the region, but follows standard methods. The 11 marks reflect multiple steps rather than conceptual difficulty. Slightly above average due to the integration of multiple techniques and the geometric visualization required, but well within expected C2 scope.
Spec1.07i Differentiate x^n: for rational n and sums1.07m Tangents and normals: gradient and equations1.08e Area between curve and x-axis: using definite integrals

Fig. 10 shows a sketch of the curve \(y = x^2 - 4x + 3\). The point A on the curve has \(x\)-coordinate 4. At point B the curve crosses the \(x\)-axis. \includegraphics{figure_2}
  1. Use calculus to find the equation of the normal to the curve at A and show that this normal intersects the \(x\)-axis at C (16, 0). [6]
  2. Find the area of the region ABC bounded by the curve, the normal at A and the \(x\)-axis. [5]

Question 2:
AnswerMarks Guidance
2(i) at A y = 3
dy
2x4
dx
dy
their  244
dx
grad of normal = –1/
their 4
y  3 = (1/ ) × (x  4) oe isw
4
substitution of y = 0 and completion to
given result with at least 1 correct interim
AnswerMarks
step wwwB1
B1
M1*
M1dep*
A1
A1
AnswerMarks
[6]must follow from attempt at differentiation
or substitution of x = 16 to obtain y = 0correct interim step may occur before
substitution
AnswerMarks Guidance
2(ii) at B, x = 3
x3 4x2
F[x]  3x
3 2
F[ 4]  F[their 3]
area of triangle = 18 soi
1
area of region = 19 oe isw
AnswerMarks
3B1
M1*
M1*
dep
B1
A1
AnswerMarks
[5]may be embedded
condone one error, must be three terms,
ignore + c
dependent on integration attempted
AnswerMarks
19.3 or bettermay be embedded in final answer
Question 2:
2 | (i) | at A y = 3
dy
2x4
dx
dy
their  244
dx
grad of normal = –1/
their 4
y  3 = (1/ ) × (x  4) oe isw
4
substitution of y = 0 and completion to
given result with at least 1 correct interim
step www | B1
B1
M1*
M1dep*
A1
A1
[6] | must follow from attempt at differentiation
or substitution of x = 16 to obtain y = 0 | correct interim step may occur before
substitution
2 | (ii) | at B, x = 3
x3 4x2
F[x]  3x
3 2
F[ 4]  F[their 3]
area of triangle = 18 soi
1
area of region = 19 oe isw
3 | B1
M1*
M1*
dep
B1
A1
[5] | may be embedded
condone one error, must be three terms,
ignore + c
dependent on integration attempted
19.3 or better | may be embedded in final answer
Fig. 10 shows a sketch of the curve $y = x^2 - 4x + 3$. The point A on the curve has $x$-coordinate 4. At point B the curve crosses the $x$-axis.

\includegraphics{figure_2}

\begin{enumerate}[label=(\roman*)]
\item Use calculus to find the equation of the normal to the curve at A and show that this normal intersects the $x$-axis at C (16, 0). [6]

\item Find the area of the region ABC bounded by the curve, the normal at A and the $x$-axis. [5]
\end{enumerate}

\hfill \mbox{\textit{OCR MEI C2  Q2 [11]}}