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Mathematics
Mathematics
Problem
Without carrying out any arithmetic calculation, decide whether the value of
cos
50
∘
cos
25
∘
+
sin
50
∘
sin
25
∘
\cos 50^{\circ}\cos 25^{\circ}+\sin 50^{\circ}\sin 25^{\circ}
cos
5
0
∘
cos
2
5
∘
+
sin
5
0
∘
sin
2
5
∘
is greater than, equal to, or less than
cos
25
∘
\cos 25^{\circ}
cos
2
5
∘
. Give a brief reason.
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