Find $\mathbf { a } \cdot \mathbf { b }$ , Given That

Multiple Choice

Find $\mathbf { a } \cdot \mathbf { b }$ , given that $| \mathbf { a } |$ = 2, $| \mathbf { b } |$ = 3, and the angle between a and b is $\frac { 5 \pi } { 6 }$ .

A) $3 \sqrt { 2 }$
B) 3
C) $3 \sqrt { 3 }$
D) $2 \sqrt { 3 }$
E) $- 3 \sqrt { 2 }$
F) -3

G) $- 3 \sqrt { 3 }$
H) $- 2 \sqrt { 3 }$