Use a sum-to-product identity to rewrite the expression.
-cos 56° + cos 28°
A) 2 cos 42° sin 14°
B) -2 sin 42° sin 14°
C) 2 sin 42° cos 14°
D) 2 cos 42° cos 14°

Question

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The Answer of Use a sum-to-product identity to rewrite the expression.
-cos 56° + cos 28°
A) 2 cos 42° sin 14°
B) -2 sin 42° sin 14°
C) 2 sin 42° cos 14°
D) 2 cos 42° cos 14°

Use a Sum-To-Product Identity to Rewrite the Expression