Câu hỏi trắc nghiệm (10 câu):
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- A. \(\overrightarrow{A H} \cdot \overrightarrow{B C}=0\)
- B. \((\overrightarrow{A B}, \overrightarrow{H A})=150^{\circ}\)
- C. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=\frac{a^{2}}{2}\)
- D. \(\overrightarrow{A C} \cdot \overrightarrow{C B}=-\frac{a^{2}}{2}\)
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- A. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=\frac{1}{2} a^{2}\)
- B. \(\overrightarrow{A C} \cdot \overrightarrow{C B}=-\frac{1}{2} a^{2}\)
- C. \(\overrightarrow{G A} \cdot \overrightarrow{G B}=\frac{a^{2}}{6}\)
- D. \(\overrightarrow{A B} \cdot \overrightarrow{A G}=\frac{1}{2} a^{2}\)
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- A. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=a^{2}\)
- B. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=\frac{a^{2} \sqrt{3}}{2}\)
- C. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=-\frac{a^{2}}{2}\)
- D. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=\frac{a^{2}}{2}\)
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- A. \(\alpha=90^{\circ}\)
- B. \(\alpha=180^{\circ}\)
- C. \(\alpha=60^{\circ}\)
- D. \(\alpha=45^{\circ}\)
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- A. \(\vec{a} \cdot \vec{b}=|\vec{a}| \cdot|\vec{b}|\)
- B. \(\vec{a} \cdot \vec{b}=0\)
- C. \(\vec{a} \cdot \vec{b}=-1\)
- D. \(\vec{a} \cdot \vec{b}=-|\vec{a}| \cdot|\vec{b}|\)
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- A. \(\alpha=30^{\circ}\)
- B. \(\alpha=45^{\circ}\)
- C. \(\alpha=60^{\circ}\)
- D. \(\alpha=120^{\circ}\)
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- A. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=2 a^{2}\)
- B. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=-\frac{a^{2} \sqrt{3}}{2}\)
- C. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=-\frac{a^{2}}{2}\)
- D. \(\overrightarrow{A B} \cdot \overrightarrow{A C}=\frac{a^{2}}{2}\)
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- A. \(\overrightarrow{C A} \cdot \overrightarrow{C B}=13\)
- B. \(\overrightarrow{C A} \cdot \overrightarrow{C B}=15\)
- C. \( \overrightarrow{C A} \cdot \overrightarrow{C B}=17\)
- D. \(\overrightarrow{C A} \cdot \overrightarrow{C B}=19\)
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- A. \(\overrightarrow{B A} \cdot \overrightarrow{B C}=b^{2}\)
- B. \( \overrightarrow{B A} \cdot \overrightarrow{B C}=c^{2}\)
- C. \(\overrightarrow{B A} \cdot \overrightarrow{B C}=b^{2}+c^{2}\)
- D. \(\overrightarrow{B A} \cdot \overrightarrow{B C}=b^{2}-c^{2}\)
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- A. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=-a^{2}\)
- B. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=a^{2}\)
- C. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=-\frac{a^{2} \sqrt{2}}{2}\)
- D. \(\overrightarrow{A B} \cdot \overrightarrow{B C}=\frac{a^{2} \sqrt{2}}{2}\)
