Soal Ulangan Harian Vektor bagian 01
Ayouk berlatih persiapan ulangan harian vektor bagian 01.
Salahsatu alternatif untuk mempersiapkan ulangan di sekolah adalah belajar dari bentuk soal yang sudah pernah diujikan sebelumnya. Cara belajar seperti ini akan menciptakan persiapan yag lebih terarah, lebih fokus dan lebih efektif.
💦 Soal No. 01.
- (A) (1, -3)
- (B) (1, 3)
- (C) (-1, -3)
- (D) (-3, -1)
- (E) (-3, -1)
Pembahasan
\(\begin{array}{l}\overline {AB} = B - A\\ = \left( {\begin{array}{*{20}{c}}2\\{ - 5}\end{array}} \right) - \left( {\begin{array}{*{20}{c}}1\\{ - 2}\end{array}} \right)\\ = \left( {\begin{array}{*{20}{c}}1\\{ - 3}\end{array}} \right)\end{array}\)
💥 Kunci Jawabn A
💦 Soal No. 02.
- (A) (-1, -5)
- (B) (1, 5)
- (C) (1, -5)
- (D) (-5, -1)
- (E) (-5, 1)
Pembahasan
\(\begin{array}{l}\overline {QP} = P - Q\\ = \left( {\begin{array}{*{20}{c}}0\\{ - 2}\end{array}} \right) - \left( {\begin{array}{*{20}{c}}1\\3\end{array}} \right)\\ = \left( {\begin{array}{*{20}{c}}{ - 1}\\{ - 5}\end{array}} \right)\end{array}\)
💥 Kunci Jawaban A
💦 Soal No. 03
- (A) (-1, -3)
- (B) (1, 3)
- (C) (-1, 3)
- (D) (1, -3)
- (E) (3, 1)
Pembahasan
\(\begin{array}{l}\overline {PQ} = Q - P\\\left( {\begin{array}{*{20}{c}}3\\{ - 1}\end{array}} \right) = \left( {\begin{array}{*{20}{c}}2\\{ - 4}\end{array}} \right) - P\\P = \left( {\begin{array}{*{20}{c}}2\\{ - 4}\end{array}} \right) - \left( {\begin{array}{*{20}{c}}3\\{ - 1}\end{array}} \right)\\ = \left( {\begin{array}{*{20}{c}}{ - 1}\\{ - 3}\end{array}} \right)\end{array}\)
💥 Kunci Jawaban A
💦 Soal No. 04.
- (A) (-6, 3)
- (B) (6, 3)
- (C) (-6, -3)
- (D) (-3, -6)
- (E) (3, -6)
Pembahasan
\(\begin{array}{l}\overline {KL} = L - K = \left( {0,2} \right)\\{\underline {\overline {JK} = K - L = \left( {2,5} \right)} _{\,\, + }}\\L - J = \left( {2,7} \right)\\J = L - \left( {2,7} \right)\\ \Rightarrow J = \left( {\begin{array}{*{20}{c}}{ - 2}\\7\end{array}} \right) - \left( {\begin{array}{*{20}{c}}2\\7\end{array}} \right) = \left( {\begin{array}{*{20}{c}}{ - 4}\\0\end{array}} \right)\\ \Rightarrow IJ = J - I\\ = \left( {\begin{array}{*{20}{c}}{ - 4}\\0\end{array}} \right) - \left( {\begin{array}{*{20}{c}}2\\3\end{array}} \right) = \left( {\begin{array}{*{20}{c}}{ - 6}\\{ - 3}\end{array}} \right)\end{array}\)
💥 Kunci Jawaban C
💦 Soal No.05.
- (A) (-1, -1)
- (B) (1, -1)
- (C) (-1, 1)
- (D) (-1, 0)
- (E) (0, -1)
Pembahasan
\(\begin{array}{l}\overline r = \overline {QP} = P - Q\\ = \left( {\begin{array}{*{20}{c}}2\\2\end{array}} \right) - \left( {\begin{array}{*{20}{c}}3\\3\end{array}} \right) = \left( {\begin{array}{*{20}{c}}{ - 1}\\{ - 1}\end{array}} \right)\end{array}\)
💥 Kunci Jawaban A
- (A) \(\left( {\begin{array}{*{20}{c}}4\\{ - 9}\end{array}} \right)\)
- (B) \(\left( {\begin{array}{*{20}{c}}-4\\{ - 9}\end{array}} \right)\)
- (C) \(\left( {\begin{array}{*{20}{c}}4\\{ 9}\end{array}} \right)\)
- (D) \(\left( {\begin{array}{*{20}{c}}9\\{ - 4}\end{array}} \right)\)
- (E) \(\left( {\begin{array}{*{20}{c}}-9\\{ - 4}\end{array}} \right)\)
Pembahasan
\(\begin{array}{l}\overline s = i + 3j\\\overline t = 2i + 5j\\ \Rightarrow 2\overline s - 3\overline t = 2\left( {\begin{array}{*{20}{c}}1\\3\end{array}} \right) - 3\left( {\begin{array}{*{20}{c}}2\\5\end{array}} \right)\\ = \left( {\begin{array}{*{20}{c}}2\\6\end{array}} \right) - \left( {\begin{array}{*{20}{c}}6\\{15}\end{array}} \right) = \left( {\begin{array}{*{20}{c}}{ - 4}\\{ - 9}\end{array}} \right)\end{array}\)
Kunci Jawaban B
💦 Soal No. 07.
- (A) 1
- (B) 2
- (C) -1
- (D) \( \pm 1\)
- (E) \( \pm 2\)
Pembahasan
\(\begin{array}{l} \Rightarrow \left| {\overline p } \right| = \sqrt {{{\left( { - 2} \right)}^2} + {1^2}} = \sqrt 5 \\ \Rightarrow \left| {\overline q } \right| = \sqrt {{2^2} + {a^2}} = \sqrt {4 + {a^2}} \\ \Leftrightarrow \left| {\overline p } \right| = \left| {\overline q } \right|\\\sqrt 5 = \sqrt {4 + {a^2}} (dikuadratkan)\\5 = 4 + {a^2}\\{a^2} = 1\,\,\,\,\, \to \,\,\,\,\,\,\,\,a = \pm 1\end{array}\)
💥 Kunci Jawaban D
💦 Soal No. 08.
- (A) \(\overline u + \overline v \)
- (B) \(\overline u - \overline v \)
- (C) \(\overline -u + \overline -v \)
- (D) \(\overline -u + \overline v \)
- (E) \(\overline -u + \overline 2v \)
💦 Soal No.09.
- (A) \(\overline a \)
- (B) \(\overline c \)
- (C) \(\overline b \)
- (D) \(\overline d \)
- (E) \(\overline -d \)
Pembahasan:
\(\begin{array}{l}*)\,\,\, - \,\overline d + \overline e = \overline g \\*)\,\,\,\overline g - \,\overline h = 2\,\overline g \\*)\,\,\overline b + \,\overline a = 2\,\overline g \\ \Rightarrow 2\,\overline g - \overline b = \overline a \end{array}\) jadi \( - \,\overline d + \overline e - \,\overline h - \overline b = \overline a \)
💥 Kunci Jawaban A
💦 Soal No. 10.
- (A) 15
- (B) 17
- (C) 20
- (D) 23
- (E) 25
Pembahasan
\(\begin{array}{l}\overline d = \overline a + \overline b + \overline c \\\overline d = \left( {\begin{array}{*{20}{c}}3\\2\end{array}} \right) + \left( {\begin{array}{*{20}{c}}{ - 8}\\9\end{array}} \right) + \left( {\begin{array}{*{20}{c}}{12}\\{13}\end{array}} \right) = \left( {\begin{array}{*{20}{c}}7\\{24}\end{array}} \right)\\\overline d = \sqrt {{7^2} + {{24}^2}} = 25\end{array}\)
💥 Kunci Jawaban E
💦 Soal No.11.
- (A) \(3i + 2j\)
- (B) \(3i - 2j\)
- (C) \(2i - 3j\)
- (D) \(2i + 3j\)
- (E) \(2i - 2j\)
Pembahasan
\(\begin{array}{l}\overline a = i - j\\{\underline {\overline b = 2i + 3j} _{\, + }}\\\overline a + \overline b = 3i + 2j\end{array}\)
💥 Kunci Jawaban A
💦 Soal No. 12
- (A) -3
- (B) -2
- (C) -1
- (D) 1
- (E) 2
Pembahasan
\(\begin{array}{l}*)\,\,\,\overline a = 3i - 2j,\,\,\,\overline b = - i + 4j\,\,dan\\\,\,\overline r = k\overline a + m\overline b \\\left( {\begin{array}{*{20}{c}}7\\{ - 8}\end{array}} \right) = k\left( {\begin{array}{*{20}{c}}3\\{ - 2}\end{array}} \right) + m\left( {\begin{array}{*{20}{c}}{ - 1}\\4\end{array}} \right)\\*)\,\,\,7 = 3k - m \to (kali4)\\28 = 12k - 4m\,\,...\,\,i)\\{\underline { - 8 = - 2k + 4m} _{\, + }}\,\,...\,\,ii)\\20 = 10k\,\, \to \,\,k = 2\\i)\,\,m = 3(2) - 7 = - 1\\ \Leftrightarrow k + m = 2 - 1 = 1\end{array}\)
💥 Kunci Jawaban D
💦 Soal No.13.
- (A) -4
- (B) -2
- (C) -1
- (D) 1
- (E) 3
Pembahasan
\(\begin{array}{l}2\left( {\begin{array}{*{20}{c}}1\\{ - 2}\end{array}} \right) + 4\left( {\begin{array}{*{20}{c}}1\\4\end{array}} \right) + m\left( {\begin{array}{*{20}{c}}2\\3\end{array}} \right) = \left( {\begin{array}{*{20}{c}}2\\6\end{array}} \right)\\2\left( 1 \right) + 4\left( 1 \right) + m\left( 2 \right) = 2\\2m = 2 - 2 - 4\\m = - \frac{4}{2} = - 2\end{array}\)
💥 Kunci Jawaban B
💦 Soal No. 14.
- (A) \({\widehat e_{\overline a }} = \frac{3}{5}i + \frac{4}{5}j\)
- (B) \({\widehat e_{\overline a }} = \frac{3}{5}i - \frac{4}{5}j\)
- (C) \({\widehat e_{\overline a }} = - \frac{3}{5}i + \frac{4}{5}j\)
- (D) \({\widehat e_{\overline a }} = \frac{3}{7}i + \frac{4}{7}j\)
- (E) \({\widehat e_{\overline a }} = \frac{3}{7}i - \frac{4}{7}j\)
Pembahasan
\(\begin{array}{l}{\widehat e_{\overline a }} = \frac{1}{{\left| {\overline a } \right|}} \cdot \overline a \\ \Rightarrow \left| {\overline a } \right| = \sqrt {{3^2} + {4^2}} = 5\\ \Leftrightarrow {\widehat e_{\overline a }} = \frac{3}{5}i + \frac{4}{5}j\end{array}\)
💥 Kunci Jawaban A
💦 Soal No. 15.
- (A) (2, 3)
- (B) (-1, 3)
- (C) (1, 3)
- (D) (-3,-1)
- (E) (3, 1)
Pembahasan
\(\begin{array}{l}\overline {AB} = \overline {DC} \\B - A = C - D\\\overline b - \overline a = \overline c - \overline d \\\overline b = \overline c - \overline d + \overline a \\\overline b = \left( {\begin{array}{*{20}{c}}{ - 4}\\3\end{array}} \right) - \left( {\begin{array}{*{20}{c}}1\\2\end{array}} \right) + \left( {\begin{array}{*{20}{c}}2\\{ - 2}\end{array}} \right)\\\overline b = \left( {\begin{array}{*{20}{c}}{ - 3}\\{ - 1}\end{array}} \right)\\B = \left( { - 3, - 1} \right)\end{array}\)
💥 Kunci Jawaban B
💦 Soal No. 16.
- (A) \(10\sqrt 3 \)
- (B) \( - 10\sqrt 3 \)
- (C) 10
- (D) -10
- (E) 20
💦 Soal No. 17.
- (A) -18
- (B) 12
- (C) -16
- (D) 18
- (E) 3
Pembahasan
\(\begin{array}{l}\overline p \cdot \overline q = 4\left( 2 \right) + 1\left( 1 \right) + 5\left( { - 5} \right)\\ = 8 + 1 - 25\\ = - 16\end{array}\)
💥 Kunci Jawaban C
💦 Soal No. 18.
- (A) \({30^o}\)
- (B) \({45^o}\)
- (C) \({60^o}\)
- (D) \({90^o}\)
- (E) \({120^o}\)
Pembahasan
\(\begin{array}{l}\overline p = - 2i + 2k\,\, \to \left| {\overline p } \right| = \sqrt {{{\left( { - 2} \right)}^2} + {2^2}} = \sqrt 8 \\\,\overline q = 2j + 2k \to \left| {\overline q } \right| = \sqrt {{2^2} + {2^2}} = \sqrt 8 \\\overline p \cdot \overline q = \left( { - 2} \right)0 + 2\left( 0 \right) + \left( 2 \right)2 = 4\\\cos \theta = \frac{4}{{\sqrt 8 \cdot \sqrt 8 }} = \frac{1}{2}\\maka\,\,\theta = {60^o}\end{array}\)
💥 Kunci Jawaban B
💦 Soal No.19.
- (A) \(\frac{5}{7}\)
- (B) \(\frac{6}{7}\)
- (C) \(\frac{2}{7}\sqrt 6 \)
- (D) \(\frac{5}{7}\sqrt 6 \)
- (E) \(\frac{6}{7}\sqrt 6 \)
Pembahasan
\(\begin{array}{l}\overline u = \left( {3, - 2,1} \right)\,\, \to \left| {\overline u } \right| = \sqrt {{{\left( 3 \right)}^2} + {{\left( { - 2} \right)}^2} + {{\left( 1 \right)}^2}} = \sqrt {14} \\\,\overline v = \left( {2, - 1,4} \right) \to \left| {\overline v } \right| = \sqrt {{{\left( 2 \right)}^2} + {{\left( { - 1} \right)}^2} + {{\left( 4 \right)}^2}} = \sqrt {21} \\\overline u \cdot \overline v = \frac{{\left( 3 \right)\left( 2 \right) + \left( { - 2} \right)\left( { - 1} \right) + \left( 1 \right)\left( 4 \right)}}{{\sqrt {14} \sqrt {21} }}\\\cos \theta = \frac{{12}}{{7\sqrt 6 }} \equiv \frac{x}{r}\end{array}\) \(\begin{array}{l}{y^2} = {r^2} - {x^2} = {\left( {7\sqrt 6 } \right)^2} - {\left( {12} \right)^2}\\y = \sqrt {294 - 144} = \sqrt {150} = 5\sqrt 6 \\maka\,\,\,\tan \theta = \frac{y}{x} = \frac{{5\sqrt 6 }}{{12}}\end{array}\)
💥 Kunci Jawaban C
💦 Soal No. 20.
- (A) \(\frac{1}{3}\)
- (B) \(\frac{1}{4}\)
- (C) \(\frac{2}{5}\)
- (D) \( - \frac{1}{3}\)
- (E) \( - \frac{2}{5}\)
Pembahasan
\(\begin{array}{l}{\left| {a + b} \right|^2} = {\left| a \right|^2} + {\left| b \right|^2} + 2\left| a \right|\left| b \right|\cos \theta \\{8^2} = {6^2} + {4^2} + 2 \cdot 6 \cdot 4\cos \theta \\48\cos \theta = 64 - 52\\\cos \theta = \frac{{12}}{{48}}\\\cos \theta = \frac{1}{4}\end{array}\)
💥 Kunci Jawaban B