Date | May Specimen paper | Marks available | 1 | Reference code | SPM.3.AHL.TZ0.2 |
Level | Additional Higher Level | Paper | Paper 3 | Time zone | Time zone 0 |
Command term | Suggest and Hence | Question number | 2 | Adapted from | N/A |
Question
This question asks you to investigate some properties of the sequence of functions of the form , −1 ≤ ≤ 1 and .
Important: When sketching graphs in this question, you are not required to find the coordinates of any axes intercepts or the coordinates of any stationary points unless requested.
For odd values of > 2, use your graphic display calculator to systematically vary the value of . Hence suggest an expression for odd values of describing, in terms of , the number of
For even values of > 2, use your graphic display calculator to systematically vary the value of . Hence suggest an expression for even values of describing, in terms of , the number of
The sequence of functions, , defined above can be expressed as a sequence of polynomials of degree .
Consider .
On the same set of axes, sketch the graphs of and for −1 ≤ ≤ 1.
local maximum points;
local minimum points;
On a new set of axes, sketch the graphs of and for −1 ≤ ≤ 1.
local maximum points;
local minimum points.
Solve the equation and hence show that the stationary points on the graph of occur at where and 0 < < .
Use an appropriate trigonometric identity to show that .
Use an appropriate trigonometric identity to show that .
Hence show that , .
Hence express as a cubic polynomial.
Markscheme
correct graph of A1
correct graph of A1
[2 marks]
graphical or tabular evidence that has been systematically varied M1
eg = 3, 1 local maximum point and 1 local minimum point
= 5, 2 local maximum points and 2 local minimum points
= 7, 3 local maximum points and 3 local minimum points (A1)
local maximum points A1
[3 marks]
local minimum points A1
Note: Allow follow through from an incorrect local maximum formula expression.
[1 mark]
correct graph of A1
correct graph of A1
[2 marks]
graphical or tabular evidence that has been systematically varied M1
eg = 2, 0 local maximum point and 1 local minimum point
= 4, 1 local maximum points and 2 local minimum points
= 6, 2 local maximum points and 3 local minimum points (A1)
local maximum points A1
[3 marks]
local minimum points A1
[1 mark]
M1A1
Note: Award M1 for attempting to use the chain rule.
M1
A1
leading to
( and 0 < < ) AG
[4 marks]
M1
stating that A1
so AG
[2 marks]
A1
use of cos(A + B) = cos A cos B − sin A sin B leading to M1
AG
[2 marks]
A1
M1
A1
AG
[3 marks]
(M1)
A1
[2 marks]