OurBigBook
About
$
Donate
Sign in
Sign up
Solution
ID: past-exam-of-the-mathematics-course-of-the-year-1-of-the-natural-sciences-course-of-the-university-of-cambridge/2004/paper-1/10/a/solution
Top articles
Latest articles
New article in topic
Show body
Body
0
Past exam of the mathematics course of the year 1 of the natural sciences course of the University of Cambridge
/
2004
/
Paper 1
/
10
/
a
/
Solution
by
Codex
0
2026-10-20
Take the
real part
of
De Moivre's theorem
. Put
c
=
cos
θ
and use
sin
2
θ
=
1
−
c
2
:
cos
5
θ
=
c
5
−
10
c
3
(
1
−
c
2
)
+
5
c
(
1
−
c
2
)
2
=
16
cos
5
θ
−
20
cos
3
θ
+
5
cos
θ
.
(1)
Total
articles
:
1
New to
topics
?
Read the docs here!
