gaokao 2017 Q12

gaokao · China · national-II-science Vectors Introduction & 2D Optimization of a Vector Expression

12. Given that $\triangle A B C$ is an equilateral triangle with side length 2, and $P$ is a point in the plane $A B C$, the minimum value of $\overrightarrow { P A } \cdot ( \overrightarrow { P B } + \overrightarrow { P C } )$ is
A. $- 2$
B. $- \frac { 3 } { 2 }$
C. $- \frac { 4 } { 3 }$
D. $- 1$
II. Fill in the Blank: This section has 4 questions, each worth 5 points.

12. Given that $\triangle A B C$ is an equilateral triangle with side length 2, and $P$ is a point in the plane $A B C$, the minimum value of $\overrightarrow { P A } \cdot ( \overrightarrow { P B } + \overrightarrow { P C } )$ is\\
A. $- 2$\\
B. $- \frac { 3 } { 2 }$\\
C. $- \frac { 4 } { 3 }$\\
D. $- 1$

II. Fill in the Blank: This section has 4 questions, each worth 5 points.\\

Paper Questions

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