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Mathematics
Mathematics
Problem
Prove that
cos
10
∘
+
sin
10
∘
cos
10
∘
−
sin
10
∘
=
tan
55
∘
\frac{\cos 10^\circ + \sin 10^\circ}{\cos 10^\circ - \sin 10^\circ} = \tan 55^\circ
c
o
s
1
0
∘
−
s
i
n
1
0
∘
c
o
s
1
0
∘
+
s
i
n
1
0
∘
=
tan
5
5
∘
.
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