Question 1
6 marks
A probability distribution with an unknown probability
- Statistics and probability
(a)
2 marks
Add the probabilities.
(b)
2 marks
The values larger than 1.5 are 2, 3 and 4.
(c)
2 marks
Use .

Worked solutions
Mathematics: Analysis & Approaches, Standard Level
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Questions 1–6 · 35 marks
Question 1
6 marks
(a)
2 marks
Add the probabilities.
(b)
2 marks
The values larger than 1.5 are 2, 3 and 4.
(c)
2 marks
Use .
Question 2
5 marks
5 marks
Question 3
5 marks
5 marks
Question 4
6 marks
(a)
2 marks
Use the multiplication rule with and .
(b)
4 marks
Question 5
8 marks
(a)
3 marks
(b)
5 marks
Question 6
5 marks
5 marks
Questions 7–9 · 45 marks
Question 7
14 marks
(a)
3 marks
Use the cosine rule in triangle .
(b)
5 marks
(c)
6 marks
(i) Put .
A length must be positive, and needs , so .
(ii) The sides are and .
Question 8
15 marks
(a)
2 marks
(b)
3 marks
(i) With , . The axis is at .
(ii) Substitute .
(c)
5 marks
(d)
5 marks
Question 9
16 marks
(a)
6 marks
(i) At : .
(ii) Set , which needs the numerator to be zero (the denominator is always positive).
(b)
1 mark
The maximum value is at , with , and the function falls towards as grows.
(c)
3 marks
(d)
6 marks
Our analysis
Each part sorted by the topic it mostly tests. Calculus carries the most marks on this paper.
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