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Mathematics
Mathematics
Problem
(i) Rewrite the expression
cos
2
x
+
cos
6
x
\cos 2x+\cos 6x
cos
2
x
+
cos
6
x
in product form. (ii) Hence solve the equation
cos
2
x
+
cos
6
x
=
0
\cos 2x+\cos 6x=0
cos
2
x
+
cos
6
x
=
0
for all real
x
x
x
.
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