Find the exact value of the expression.
-$\cos \left( \frac { 5 \pi } { 18 } \right) \cos \left( \frac { 2 \pi } { 9 } \right) - \sin \left( \frac { 5 \pi } { 18 } \right) \sin \left( \frac { 2 \pi } { 9 } \right)$
A) $- 1$
B) 1
C) 0
D) $\frac { \sqrt { 2 } } { 2 }$

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The Answer of Find the exact value of the expression.
-$\cos \left( \frac { 5 \pi } { 18 } \right) \cos \left( \frac { 2 \pi } { 9 } \right) - \sin \left( \frac { 5 \pi } { 18 } \right) \sin \left( \frac { 2 \pi } { 9 } \right)$
A) $- 1$
B) 1
C) 0
D) $\frac { \sqrt { 2 } } { 2 }$

Find the Exact Value of the Expression A) −1- 1−1 B) 1 C) 0 D)

Find the Exact Value of the Expression A) $- 1$ B) 1
C) 0
D)