Use Identities to find the exact value.
-$$\cos \frac { 7 \pi } { 12 } \cos \frac { 5 \pi } { 12 } + \sin \frac { 7 \pi } { 12 } \sin \frac { 5 \pi } { 12 }$$
A) - 1
B) $\frac { 1 } { 2 }$
C) $\frac { \sqrt { 2 } } { 2 }$
D) $\frac { \sqrt { 3 } } { 2 }$

Question

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The Answer of Use Identities to find the exact value.
-$$\cos \frac { 7 \pi } { 12 } \cos \frac { 5 \pi } { 12 } + \sin \frac { 7 \pi } { 12 } \sin \frac { 5 \pi } { 12 }$$
A) - 1
B) $\frac { 1 } { 2 }$
C) $\frac { \sqrt { 2 } } { 2 }$
D) $\frac { \sqrt { 3 } } { 2 }$

Use Identities to Find the Exact Value cos⁡7π12cos⁡5π12+sin⁡7π12sin⁡5π12\cos \frac { 7 \pi } { 12 } \cos \frac { 5 \pi } { 12 } + \sin \frac { 7 \pi } { 12 } \sin \frac { 5 \pi } { 12 }cos127π​cos125π​+sin127π​sin125π​

Use Identities to Find the Exact Value $\cos \frac { 7 \pi } { 12 } \cos \frac { 5 \pi } { 12 } + \sin \frac { 7 \pi } { 12 } \sin \frac { 5 \pi } { 12 }$