CAIE P1 2016 November — Question 7 7 marks

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2016
SessionNovember
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicAreas Between Curves
TypeParametric or Inverse Function Area
DifficultyStandard +0.3 This question requires finding intersection points and calculating area between curves. Part (i) is straightforward substitution to find point A. Part (ii) involves setting up and evaluating a definite integral, requiring students to express both curves as functions of y (since one is already in that form), find limits, and integrate. While it tests multiple skills (solving equations, curve sketching understanding, integration), these are all standard A-level techniques with no novel insight required. The working is methodical rather than conceptually challenging.
Spec1.02q Use intersection points: of graphs to solve equations1.08f Area between two curves: using integration

7 \includegraphics[max width=\textwidth, alt={}, center]{9f17f7b8-b54d-467d-be26-21c599ce6ca2-3_704_558_258_790} The diagram shows parts of the curves \(y = ( 2 x - 1 ) ^ { 2 }\) and \(y ^ { 2 } = 1 - 2 x\), intersecting at points \(A\) and \(B\).
  1. State the coordinates of \(A\).
  2. Find, showing all necessary working, the area of the shaded region.

Question 7:
Part (i):
AnswerMarks Guidance
\(A = (\frac{1}{2}, 0)\)B1 [1] Accept \(x = 0\) at \(y = 0\)
Part (ii):
AnswerMarks Guidance
\(\int(1-2x)^{\frac{1}{2}}\,dx = \left[\dfrac{(1-2x)^{3/2}}{3/2}\right] \div (-2)\)B1B1 May be seen in a single expression
\(\int(2x-1)^2\,dx = \left[\dfrac{(2x-1)^3}{3}\right] \div 2\)B1B1 May use \(\int_a^{\cdot} x\,dy\), may expand \((2x-1)^2\)
\([0-(-1/3)] - [0-(-1/6)]\)M1 Correct use of *their* limits
\(1/6\)A1 [6]
## Question 7:

### Part (i):
$A = (\frac{1}{2}, 0)$ | **B1** [1] | Accept $x = 0$ at $y = 0$

### Part (ii):
$\int(1-2x)^{\frac{1}{2}}\,dx = \left[\dfrac{(1-2x)^{3/2}}{3/2}\right] \div (-2)$ | **B1B1** | May be seen in a single expression
$\int(2x-1)^2\,dx = \left[\dfrac{(2x-1)^3}{3}\right] \div 2$ | **B1B1** | May use $\int_a^{\cdot} x\,dy$, may expand $(2x-1)^2$
$[0-(-1/3)] - [0-(-1/6)]$ | **M1** | Correct use of *their* limits
$1/6$ | **A1** [6] |

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7\\
\includegraphics[max width=\textwidth, alt={}, center]{9f17f7b8-b54d-467d-be26-21c599ce6ca2-3_704_558_258_790}

The diagram shows parts of the curves $y = ( 2 x - 1 ) ^ { 2 }$ and $y ^ { 2 } = 1 - 2 x$, intersecting at points $A$ and $B$.\\
(i) State the coordinates of $A$.\\
(ii) Find, showing all necessary working, the area of the shaded region.

\hfill \mbox{\textit{CAIE P1 2016 Q7 [7]}}