Date | May Specimen paper | Marks available | 3 | Reference code | SPM.1.AHL.TZ0.15 |
Level | Additional Higher Level | Paper | Paper 1 | Time zone | Time zone 0 |
Command term | Draw | Question number | 15 | Adapted from | N/A |
Question
Let w=aeπ4i, where a∈R+.
for a = 2,
find the values of w2, w3, and w4.
[2]
a.i.
draw w, w2, w3, and w4 on the following Argand diagram.
[3]
a.ii.
Let z=w2−i.
Find the value of a for which successive powers of z lie on a circle.
[2]
b.
Markscheme
4eπ2i, 8e3π4i, 16eπi (=4i, −4√2+4√2i, −16) (M1)A1
[2 marks]
a.i.
A3
Note: Award A1 for correct arguments, award A1 for 4i and −16 clearly indicated, award A1 for | w | < 4 and 4 < | w3 | < 16.
[3 marks]
a.ii.
22+12=a2 M1
a=√5(=2.24) A1
[2 marks]
b.
Examiners report
[N/A]
a.i.
[N/A]
a.ii.
[N/A]
b.