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Romania Team Selection Test
1978 Romania Team Selection Test
4
trigonometric equation in two variables
trigonometric equation in two variables
Source: Romanian TST 1978, Day 3, P4
September 30, 2018
trigonometry
trigonometric equation
equations
algebra
Problem Statement
Solve the equation
sin
x
sin
2
x
⋯
sin
n
x
+
cos
x
cos
2
x
⋯
cos
n
x
=
1
,
\sin x\sin 2x\cdots\sin nx+\cos x\cos 2x\cdots\cos nx =1,
sin
x
sin
2
x
⋯
sin
n
x
+
cos
x
cos
2
x
⋯
cos
n
x
=
1
,
for
n
∈
N
n\in\mathbb{N}
n
∈
N
and
x
∈
R
.
x\in\mathbb{R} .
x
∈
R
.
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