arthham

Exam

Cambridge A Level Mathematics

Conducting Body
Cambridge Assessment International Education (CAIE)
For
Pre-university students, typically ages 16-19
Papers
Pure Mathematics, Mechanics, and Probability & Statistics
Question Format
Structured questions requiring detailed working
Paper Duration
Varies by paper, approx. 1.5 to 2 hours each
Exam Sessions
Twice a year (June and November series)
Qualifies For
University admission, especially for STEM and economics

Cambridge A Level Mathematics is a pre-university qualification for students aged 16 to 19. It is taken by those planning to pursue degrees in science, technology, engineering, mathematics (STEM), economics, or computer science, as it is a common prerequisite for these courses at universities worldwide. The qualification demonstrates a high level of mathematical ability and is highly regarded by admissions tutors.

The examination consists of several written papers, typically covering Pure Mathematics, Mechanics, and Probability & Statistics. Students must answer structured questions, showing their working clearly to gain full marks. The challenge of A Level Mathematics comes from the need to apply familiar concepts to new and complex problems. Simple recall of formulas is insufficient. Success depends on a deep conceptual understanding, strong algebraic manipulation skills, and the ability to construct logical arguments under time pressure. The step up in abstract thinking and problem-solving from previous qualifications is significant.

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JEE Advanced 2023

Let f:[0,1]→[0,1]f : [0,1] \to [0,1] be the function defined by f(x)=x33−x2+59x+1736f(x) = \frac{x^3}{3} - x^2 + \frac{5}{9}x + \frac{17}{36} . Consider the square region S=[0,1]×[0,1]S = [0,1]\times[0,1] . Let G={(x,y)∈S:y>f(x)}G = \{(x,y) \in S : y > f(x)\} be called the green region and R={(x,y)∈S:y<f(x)}R = \{(x,y) \in S : y < f(x)\} be called the red region. Let Lh={(x,h)∈S:x∈[0,1]}L_h = \{(x,h) \in S : x \in [0,1]\} be the horizontal line drawn at a height h∈[0,1]h \in [0,1] . Then which of the following statements is(are) true?
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f(x)=x33−x2+59x+1736,x∈[0,1]f(x) = \dfrac{x^3}{3} - x^2 + \dfrac{5}{9}x + \dfrac{17}{36}, \quad x \in [0,1]

S=[0,1]2;G:y>f(x) (green);R:y<f(x) (red);Lh:y=hS = [0,1]^2;\quad G: y > f(x)\ \text{(green)};\quad R: y < f(x)\ \text{(red)};\quad L_h: y = h

To find: which statements (1)–(4) are true\text{To find: which statements (1)--(4) are true}

f′(x)=x2−2x+59=(x−13)(x−53)f'(x) = x^2 - 2x + \dfrac{5}{9} = (x-\tfrac13)(x-\tfrac53)

∫01f(x) dx=112−13+518+1736=12\int_0^1 f(x)\,dx = \dfrac{1}{12} - \dfrac13 + \dfrac{5}{18} + \dfrac{17}{36} = \dfrac12

⇒area⁡(R)=area⁡(G)=12\Rightarrow \operatorname{area}(R) = \operatorname{area}(G) = \dfrac12

AG<+AR<=h,AG>+AR>=1−hA_G^< + A_R^< = h, \qquad A_G^> + A_R^> = 1 - h

AG<+AG>=12,AR<+AR>=12A_G^< + A_G^> = \dfrac12, \qquad A_R^< + A_R^> = \dfrac12

AG>−AR<=12−h,AR>−AG<=12−hA_G^> - A_R^< = \dfrac12 - h, \qquad A_R^> - A_G^< = \dfrac12 - h

h=12⇒AG>=AR< and AR>=AG<⇒(3),(4) TRUEh = \dfrac12 \Rightarrow A_G^> = A_R^< \text{ and } A_R^> = A_G^< \Rightarrow (3), (4)\ \text{TRUE}

(2): AR>=AR<  ⟺  AR<=14(2):\ A_R^> = A_R^< \iff A_R^< = \dfrac14

f(x)≥1336>14⇒AR< ⁣(14)=14⇒(2) TRUEf(x) \ge \dfrac{13}{36} > \dfrac14 \Rightarrow A_R^<\!\left(\dfrac14\right) = \dfrac14 \Rightarrow (2)\ \text{TRUE}

(1): AG>=AG<  ⟺  AG<=14(1):\ A_G^> = A_G^< \iff A_G^< = \dfrac14

f(x)<23⇒AG< ⁣(23)=23−12=16<14⇒(1) FALSEf(x) < \dfrac23 \Rightarrow A_G^<\!\left(\dfrac23\right) = \dfrac23 - \dfrac12 = \dfrac16 < \dfrac14 \Rightarrow (1)\ \text{FALSE}

TRUE: (2), (3), (4)\text{TRUE: } (2),\ (3),\ (4)

(2), (3), (4)\boxed{(2),\ (3),\ (4)}

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