Soal dan Pembahasan Matematika IPA SNMPTN 2013 (Kode 138)
Bimbel WIN:
- Matematika IPA -
💦 Soal No.01
Persamaan lingkaran dengan pusat (-1, 1) dan menyinggung garis \(3x - 4y + 12 = 0\) adalah ...
(A) \({x^2} + {y^2} + 2x - 2y + 1{\rm{ }} = {\rm{ }}0\)
(B) \({x^2} + {y^2} + 2x - 2y - 7 = 0\)
(C) \(4{x^2} + 4{y^2} + 8x - 8y - 17 = 0\)
(D) \({x^2} + {y^2} + 2x - 2y - 2 = 0\)
(E) \(4{x^2} + 4{y^2} + 8x - 8y - 1 = 0\)
Pembahasan:
\(g = 3x - 4y + 12 = 0\)
\(\begin{array}{l}r = \left| {\frac{{3( - 1) - 4(1) + 12}}{{\sqrt {{3^2} + {{( - 4)}^2}} }}} \right|\\r = \left| {\frac{{ - 3 - 4 + 12}}{{\sqrt {9 + 16} }}} \right|\end{array}\)
\(\begin{array}{l}{\rm{L}}\, \equiv \,\,\,\,\,\,\,\,\,{\left( {{\rm{x}} - {\rm{a}}} \right)^2} + {\left( {{\rm{y}} - {\rm{b}}} \right)^2}\,\, = {{\rm{r}}^2}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\left( {{\rm{x}} + 1} \right)^2} + {\left( {{\rm{y}} - 1} \right)^2}\,\,\,\, = {1^2}\\\,\,\,{{\rm{x}}^2} + 2x + 1 + {{\rm{y}}^2} - 2{\rm{y + 1 = 1}}\\\,\,\,{{\rm{x}}^{\rm{2}}} + {{\rm{y}}^2} + 2{\rm{x}} - 2{\rm{y}} + 1\,\,\,\,\,\,\,\,\, = 0\end{array}\)
💥Kunci Jawaban: A
Pembahasan:
\(\begin{array}{l}{\rm{co}} + {105^ \circ }\,\,.\,\,{\rm{tan}}\,\,{15^ \circ } = \frac{{\cos \,{{105}^ \circ }}}{{\sin \,{{105}^ \circ }}}\,\,{\rm{x}}\,\,\frac{{\sin \,{{15}^ \circ }}}{{\cos \,{{15}^ \circ }}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{\left( {\sin \left( {{{105}^ \circ } + {{15}^ \circ }} \right) - \sin \left( {{{105}^ \circ } - {{15}^ \circ }} \right)} \right)}}{{\left( {\sin \left( {{{105}^ \circ } + {{15}^ \circ }} \right) + \sin \left( {{{105}^ \circ } - {{15}^ \circ }} \right)} \right)}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{\sin \,\,\,{{120}^ \circ } - \sin \,\,\,{{90}^ \circ }}}{{\sin \,\,\,{{120}^ \circ } + \sin \,\,\,{{90}^ \circ }}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{\left( {\sin \,{{60}^ \circ }} \right) - 1}}{{\left( {\sin \,{{60}^ \circ }} \right) + 1}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{{\textstyle{1 \over 2}}\sqrt 3 - 1}}{{{\textstyle{1 \over 2}}\sqrt 3 + 1}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{\sqrt 3 - 2}}{{\sqrt 3 + 2}}\,\,\,{\rm{x}}\,\,\,\frac{{\sqrt 3 - 2}}{{\sqrt 3 - 2}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{3 - 2\sqrt 3 - 2\sqrt 3 + 4}}{{3 - 4}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{7 - 4\sqrt 3 }}{{ - 1}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = - 7 + 4\sqrt 3 \end{array}\)
💥Kunci Jawaban: A
💦 Soal No.03
Pembahasan:
L = laki-laki
P = Perempuan
\(\begin{array}{l}{\rm{n(k)}} = 4\,!\,\,\,\, \cdot \,\,\,\,3\,!\\{\rm{n(s)}} = 6\,!\\\\{\rm{P = }}\frac{{{\rm{n(k)}}}}{{{\rm{n(s)}}}}\\{\rm{P = }}\frac{{{\rm{4}}\,{\rm{!}}\,\,\,\, \cdot \,\,\,\,{\rm{3}}\,{\rm{!}}}}{{{\rm{6}}\,{\rm{!}}}}\\{\rm{P}} = \frac{{3{\rm X}\,\,2{\rm{x}}1}}{{6{\rm{x}}5}}\\{\rm{P}} = {\textstyle{1 \over 5}}\end{array}\)
💥Kunci Jawaban: E
💦 Soal No. 04
Pembahasan:
Diketahui \(\begin{array}{l}\Delta \,{\rm{ABC}}\,\,\,\,\, \to \,\,\,\,{\rm{A}} + {\rm{B}} + {\rm{C}} = 180\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{A}} + {\rm{B}} = 180 - {\rm{C}}\end{array}\)
\(\begin{array}{l}\,{\rm{(i)}}\,\,\,{\rm{3}}\,{\rm{sin}}\,{\rm A} + 4\,\cos {\rm B}\,\,\,\,\,\,\,\, = 6\\\,\,\,\,\,\,\,{\left( {3\,\sin \,{\rm A} + 4\cos {\rm B}} \right)^2} = {6^2}\\{\rm{g}}\,{\rm{si}}{{\rm{n}}^{\rm{2}}}{\rm A} + 24\sin \,{\rm A} \cdot \cos \,{\rm B} + 16{\cos ^2}{\rm B} = 36\\\,{\rm{(ii)}}\,\,\,{\rm{3}}\,{\rm{cos}}\,{\rm A}{\rm{ + 4}}\,{\rm{sin}}\,{\rm B} = \sqrt {13} \\\,\,\,\,\,\,\,{\left( {3\cos {\rm A} + 4\,\sin {\rm B}} \right)^2} = {\left( {\sqrt {13} } \right)^2}\\{\rm{g}}\,{\rm{co}}{{\rm{s}}^{\rm{2}}}{\rm A} + 24\cos {\rm A} \cdot \sin {\rm B} + 16\,{\sin ^2}{\rm B} = 13\end{array}\)
\(\begin{array}{l} \Rightarrow {\rm{g}}\,{\rm{si}}{{\rm{n}}^{\rm{2}}}{\rm A} + 24\sin {\rm{A}}{\rm{.cos}}\,{\rm{B + 16}}\,{\rm{co}}{{\rm{s}}^{\rm{2}}}{\rm{B = 36}}\\\,\,\,\,\,\,{\underline {{\rm{g}}\,{{\cos }^{\rm{2}}}{\rm A} + 24\cos {\rm{A}}\, \cdot \,{\rm{sin}}\,{\rm{B + 16}}\, \cdot \,{{\sin }^{\rm{2}}}{\rm{B = 13}}} _ + }\end{array}\)
\(\begin{array}{l}{\rm{g}}\left( {{\rm{si}}{{\rm{n}}^{\rm{2}}}{\rm{A + co}}{{\rm{s}}^{\rm{2}}}{\rm{B}}} \right){\rm{ + 24}}\left( {{\rm{sinA}}\, \cdot \,{\rm{cosB + cosA}} \cdot {\rm{sinB}}} \right){\rm{ + 16}}\left( {{\rm{si}}{{\rm{n}}^{\rm{2}}}{\rm{B + co}}{{\rm{s}}^{\rm{2}}}{\rm{B}}} \right){\rm{ = 49}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,9 + 24\sin \left( {{\rm{A}} + {\rm{B}}} \right) + 16 = 49\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,24\sin \left( {{\rm{A}} + {\rm{B}}} \right) = 24\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\sin \left( {{\rm{A}} + {\rm{B}}} \right) = 1\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\sin \left( {180 - c} \right) = 1\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\sin \,\,{\rm{c}} = 1\end{array}\)
💥Kunci Jawaban: E
💦 Soal No.05
Pembahasan:
\(\begin{array}{l}\overline {{\rm{AC}}} \,\,\, = \,\,\,{\rm{C}} - {\rm{A}}\,\,\,{\rm{ = }}\,\,\,\left[ {\begin{array}{*{20}{c}}0\\0\\8\end{array}} \right]\,\,\, - \,\,\,\left[ {\begin{array}{*{20}{c}}{ - 3}\\0\\0\end{array}} \right]\,\,\, = \,\,\,\left[ {\begin{array}{*{20}{c}}3\\0\\8\end{array}} \right]\\\overline {{\rm{AB}}} \,\,\, = \,\,\,{\rm{B}} - {\rm{A}}\,\,\,{\rm{ = }}\,\,\,\left[ {\begin{array}{*{20}{c}}0\\3\\0\end{array}} \right]\,\,\, - \,\,\,\left[ {\begin{array}{*{20}{c}}{ - 3}\\0\\0\end{array}} \right]\,\,\, = \,\,\,\left[ {\begin{array}{*{20}{c}}3\\3\\0\end{array}} \right]\end{array}\)
Panjang proy . Vektor \(\overline {{\rm{AC}}} \)
pada \(\overline {{\rm{AB}}} \)
\( = \,\,\,\frac{{\overline {{\rm{AC}}} \,\,\,.\,\,\,\overline {{\rm{AB}}} }}{{\left| {\overline {{\rm{AB}}} } \right|}}\)
\(\begin{array}{l} = \,\,\,\frac{{\left[ {\begin{array}{*{20}{c}}3\\0\\8\end{array}} \right]\,\,\,.\,\,\,\left[ {\begin{array}{*{20}{c}}3\\3\\0\end{array}} \right]}}{{\sqrt {{3^2} + {3^2} + {0^2}} }}\\ = \,\,\,\frac{{\left( {3{\rm{x}}3} \right) + \left( {0{\rm{x}}3} \right) + \left( {8{\rm{x}}0} \right)}}{{\sqrt {18} }}\\ = \,\,\,\frac{9}{{3\sqrt 2 }}\\ = \,\,\,\frac{{3\sqrt 2 }}{2}\end{array}\)
💥Kunci Jawaban: B
💦 Soal No.06
Pembahasan:
Transformasi T merupakan pencerminan terhadap garis y = -2x dilanjutkan terhadap garis y = \({\textstyle{1 \over 2}}{\rm{x}}\)
Transformasi sembarang titik oleh transformasi T sama dengan pencerminan titik tersebut terhadap titik (0,0), karena garis y = -2x dan y=\({\textstyle{1 \over 2}}{\rm{x}}\) saling tegak lurus dan berpotongan di titik (0,0)
Sehingga :
T = matriks refleksi terhadap titik (0,0)
T = \(\left[ {\begin{array}{*{20}{c}}{ - 1}&0\\0&{ - 1}\end{array}} \right]\)
💥Kunci Jawaban: E
💦 Soal No.07
Pembahasan:
\(\begin{array}{l}{\rm{TP = BP = }}\sqrt {{\rm{A}}{{\rm{T}}^2} - {\rm{A}}{{\rm{P}}^2}} \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \sqrt {{{\rm{a}}^2} - {{\left( {{\textstyle{1 \over 2}}{\rm{a}}} \right)}^2}} \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \sqrt {{{\rm{a}}^2} - {\textstyle{1 \over 4}}{{\rm{a}}^{\rm{2}}}} \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = {\textstyle{1 \over 2}}{\rm{a}}\sqrt 3 \end{array}\)
Jarak titik P ke garis BT
\(\begin{array}{l}{\rm{PO = }}\sqrt {{\rm{P}}{{\rm{T}}^2} - {\rm{O}}{{\rm{T}}^2}} \\\,\,\,\,\,\,\, = \sqrt {{{\left( {{\textstyle{1 \over 2}}{\rm{a}}\sqrt 3 } \right)}^2} - {{\left( {{\textstyle{1 \over 2}}{\rm{a}}} \right)}^2}} \\\,\,\,\,\,\,\, = \sqrt {{\textstyle{3 \over 4}}{{\rm{a}}^2} - {\textstyle{1 \over 4}}{{\rm{a}}^{\rm{2}}}} \\\,\,\,\,\,\,\, = {\textstyle{1 \over 2}}{\rm{a}}\sqrt 2 \end{array}\)
💥Kunci Jawaban: A
💦 Soal No.08
Pembahasan:
Jika \(f\left( x \right).\left( {x - 1} \right) = {x^4} + a{x^3} + \left( {b - 14} \right){x^2} + 28x - 15\)
(i) artinya (x - 1) adalah faktor linear dari suku banyak \(\left( {{{\rm{x}}^4} + {\rm{a}}{{\rm{x}}^{\rm{3}}} + \left( {{\rm{b}} - 14} \right){{\rm{x}}^2} + 28{\rm{x}} - 15} \right)\)
x = 1 \(\begin{array}{l}1\,\,\,\,a\,\,\,\,\left( {b - 14} \right)\,\,\,\,\,\,\,\,\,28\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, - 15\\{\underline {\,\,\,\,\,\,1\,\,\,\,\,\,\,\,\,a + 1\,\,\,\,\,\,a + b - 13\,\,\,\,\,a + b + 15} _ + }\\1\,\,\,\,\,\,{\rm{a}} + 1\,\,\,\,\,\,{\rm{a + b - 13}}\,\,\,\,\,{\rm{a + b + 15}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0\end{array}\)
s (x) = 0 \( \to \)-15 + a + b + 15 = 0
a + b = 0 ... pers (1)
eliminasi pers (1) dan pers (2)
\(\begin{array}{*{20}{c}}{3a + 2b = - 4}\\{a + b = 0}\end{array}\left| {\begin{array}{*{20}{c}}{{\rm{x}}\,1}\\{{\rm{x}}2}\end{array}} \right|\begin{array}{*{20}{c}}{3a + 2b = - 4}\\\begin{array}{l}\underline {2a + 2b = 0\,\, - } \\a = - 4\end{array}\end{array}\)
(ii) f(x) adalah hasil bagi suku banyak
\(\left( {{{\rm{x}}^4} + {\rm{a}}{{\rm{x}}^3} + \left( {{\rm{b}} - 14} \right){{\rm{x}}^2} + 28\,\,{\rm{x}} - 15} \right)\,\,{\rm{oleh}}\,\,\left( {{\rm{x}} - 1} \right)\)
\(\begin{array}{l}{\rm{f}}\left( {\rm{x}} \right).\left( {{\rm{x}} - 1} \right) = \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{f}}\left( {\rm{x}} \right) = \end{array}\) \(\begin{array}{l}{x^4}a{x^3} + \left( {b - 14} \right){x^2} + 28x - 15\\\underline {{{\rm{x}}^4} + {\rm{a}}{{\rm{x}}^3} + \left( {{\rm{b}} - 14} \right){{\rm{x}}^2} + 28{\rm{x}} - 15} \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {{\rm{x}} - 1} \right)\end{array}\)
( x - 1 ) merupakan faktor f (x)
x = 1 \(\begin{array}{l}1\,\,\,\,\,{\rm{a}} + 1\,\,\,\,\,{\rm{a + b}} - 13\,\,\,\,\,\,\,\,\,{\rm{a + b}} + 15\\{\underline {\,\,\,\,\,\,\,\,\,\,\,1\,\,\,\,\,\,\,\,\,\,a + 2\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2a + b - 11} _ + }\\1\,\,\,\,\,\,\,a + 2\,\,\,\,\,\,2a + b - 11\,\,\,\,\,\,\,\,\,\,\,\,\,\,0\end{array}\)
s (x) = 0 \( \to \)-15 + a + b + 15 = 0
3a + 2b = -4 pers (2)
💥Kunci Jawaban:
💦 Soal No.09
Pembahasan:
\(\mathop {\lim }\limits_{x \to 0} \,\,\,\,\,\frac{{\cos \,\,{\rm{x}} - \cos \,\,3{\rm{x}}}}{{{x^2}\,\,\,.\,\,\,\sqrt {4 - {\rm{x}}} }}\) \(\begin{array}{l} = \mathop {\lim }\limits_{x \to 0} \,\,\,\,\,\,\frac{{ - 2\, \cdot \,\,\sin \left( {{\textstyle{{{\rm{x}} + 3{\rm{x}}} \over 2}}} \right) \cdot \sin \left( {{\textstyle{{{\rm{x}} - 3{\rm{x}}} \over 2}}} \right)}}{{{\rm{x}}\,\,.\,\,{\rm{x}}\,\,.\,\,\sqrt {4 - {\rm{x}}} }}\\ = \mathop {\lim }\limits_{x \to 0} \,\,\,\,\,\,\frac{{ - 2\,.\,{{\sin }^2}\,\,2{\rm{x}}\,\,.\,\,{{\sin }^{ - 1}} - {\rm{x}}}}{{\mathop {\rm{x}}\limits_1 \,\,.\,\,\mathop {\rm{x}}\limits_1 \,\,.\sqrt {4 - {\rm{x}}} }}\\ = \mathop {\lim }\limits_{x \to 0} \,\,\,\,\,\,\frac{4}{{\sqrt {4 - {\rm{x}}} }}\\ = \frac{4}{{\sqrt {4 - 0} }}\\ = 2\,\end{array}\)
💥 Kunci Jawaban: E
💦Soal No.10
Pembahasan:
💥 Kunci Jawaban:
💦Soal No.11
Pembahasan:
\(\begin{array}{l}\int {4\,\, \cdot \,\,\sin \,{\rm{x}}\,\, \cdot {{\cos }^2}\,\,2{\rm{x}}\,\,{\rm{dx}} = \int {4\,\, \cdot \,\,\sin \,{\rm{x}}\,\, \cdot \,\,\cos \,2{\rm{x}}\,\, \cdot \cos 2{\rm{x}}\,\,{\rm{dx}}} } \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \int {4\,\, \cdot \,\,{\textstyle{1 \over 2}}\,\, \cdot \left( {\sin \,3{\rm{x}} - \sin \,{\rm{x}}} \right) \cdot \cos \,2{\rm{x}}\,\,{\rm{dx}}} \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \int {2 \cdot \sin \,3{\rm{x}} \cdot \cos \,2{\rm{x}}\,{\rm{dx}} - \int {2 \cdot \sin \,{\rm{x}} \cdot \cos \,2{\rm{x}}\,{\rm{dx}}} } \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \int {\left( {\sin \,5{\rm{x}} + \sin \,{\rm{x}}} \right){\rm{dx}} - \int {\left( {\sin \,3{\rm{x}} - \sin \,{\rm{x}}} \right){\rm{dx}}} } \\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \left( {{\textstyle{1 \over 5}}\cos \,5{\rm{x}} - \cos \,{\rm{x}}} \right) - \left( { - {\textstyle{1 \over 3}}\cos \,3{\rm{x}} + \cos \,{\rm{x}}} \right) + {\rm{c}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = - {\textstyle{1 \over 5}}\cos \,5{\rm{x}} + {\textstyle{1 \over 3}}\cos \,3{\rm{x}} - 2\,\cos \,{\rm{x}} + {\rm{c}}\end{array}\)
💥 Kunci Jawaban: D
💦 Soal No.12
Pembahasan:
Titik Potong
\(\begin{array}{l}{{\rm{y}}_{{\rm{kurva}}}} - {{\rm{y}}_{{\rm{garis}}}} = 0\\\,\,\,\,\,6 - {{\rm{x}}^2} - 5\left| {\rm{x}} \right| = 0\\\,\,\,\,\,{{\rm{x}}^2} + 5\left| {\rm{x}} \right| - 6 = 0\end{array}\)
\(\begin{array}{l}\left( {\rm{i}} \right)\,\,\,\,\,\,{{\rm{x}}^2} + 5{\rm{x}} - 6 = 0\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {{\rm{ii}}} \right)\,\,\,\,\,\,{{\rm{x}}^2} - 5{\rm{x}} - 6 = 0\\\,\,\,\,\,\,\left( {{\rm{x}} + 6} \right)\left( {{\rm{x}} - 1} \right) = 0\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {{\rm{x}} - 6} \right)\left( {{\rm{x}} + 1} \right) = 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x = 1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x = - 1\end{array}\)
\(\begin{array}{l}{\rm{L}} = 2 \cdot \int\limits_{ - 1}^0 {\left( {\left( {6 - {{\rm{x}}^2}} \right) - \left( { - 5{\rm{x}}} \right)} \right){\rm{dx}}} \\\,\,\,\, = 2\int\limits_{ - 1}^0 {\left( { - {{\rm{x}}^2} + 5{\rm{x}} + 6} \right){\rm{dx}}} \end{array}\)
💥Kunci Jawaban: C
💦 Soal No.13
Pembahasan:
Angka yang tersedia : 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 banyak bilangan ratusan
( i ) selisih antara bil. pertama dan bil. kedua = 2
\(\begin{array}{l}2\,\,{\rm{dan}}\,\,0\,|1\,|\,|1\,|\,|10\,|\, = 10\\4\,\,{\rm{dan}}\,\,2\,|1\,|\,|1\,|\,|10\,|\,\, = 10\, \times \,2 = 20\\6\,\,{\rm{dan}}\,\,4\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\\8\,\,{\rm{dan}}\,\,6\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\\3\,\,{\rm{dan}}\,\,1\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\\5\,\,{\rm{dan}}\,\,3\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\\7\,\,{\rm{dan}}\,\,5\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\\9\,\,{\rm{dan}}\,\,7\,|1\,|\,|1\,|\,|10\,|\, = 10\, \times \,2 = 20\end{array}\)
\(\begin{array}{l}3\,\,{\rm{dan}}\,\,0\,\,|1||1||10|\, = 10\\6\,\,{\rm{dan}}\,\,3\,\,|1||1||10|\, = 10\, \times \,2 = 20\\9\,\,{\rm{dan}}\,\,6\,\,|1||1||10|\, = 10\, \times \,2 = 20\\4\,\,{\rm{dan}}\,\,1\,\,|1||1||10|\, = 10\, \times \,2 = 20\\7\,\,{\rm{dan}}\,\,4\,\,|1||1||10|\, = 10\, \times \,2 = 20\\5\,\,{\rm{dan}}\,\,2\,\,|1||1||10|\, = 10\, \times \,2 = 20\\8\,\,{\rm{dan}}\,\,5\,\,|1||1||10|\, = 10\, \times \,2 = 20\end{array}\)
Total \(\begin{array}{l} = \left( {13 \times 20} \right) + \left( {2 \times 10} \right)\\ = 280\end{array}\)
💥Kunci Jawaban: B
💦 Soal No.14
Pembahasan:
\(\begin{array}{l}{\rm{F}}\left( {\rm{x}} \right) = \left( {{\rm{a}} + 1} \right){{\rm{x}}^3} - 3\,{\rm{bx}} - 9{\rm{x}}\\{{\rm{F}}^I}\left( {\rm{x}} \right) = \left( {3{\rm{a}} + 3} \right){{\rm{x}}^2} - 6{\rm{b}}\,{\rm{x}} - 9\\{{\rm{F}}^{ll}}\left( {\rm{x}} \right) = \left( {6{\rm{a}} + 6} \right){\rm{x}} - 6{\rm{b}}\end{array}\)
(i) F'' (x) habis dibagi (x + 1)
\(\begin{array}{l}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,F\left( { - 1} \right) = 0\\\left( {6a + 6} \right)\left( { - 1} \right) - 6b = 0\\{\underline {\,\,\,\,\,\,\,\,\, - 6a - 6 - 6b = 0} _{: - 6}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,a + 1 + b = 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,a = - - b\end{array}\)
Kurva F (x) tidak mempunyai titik ekstreem lokal jika turunan pertamanya hanya memiliki paling banyak 1 ekor
\(\begin{array}{l}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{F}}'\left( {\rm{x}} \right) = 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {3{\rm{a}} + 3} \right){{\rm{x}}^2} - 6\,{\rm{b}}\,{\rm{x}} - 9 = 0\\\left( {3\left( { - 1 - {\rm{b}}} \right) + 3} \right){{\rm{x}}^2} - 6{\rm{b}}\,{\rm{x}} - 9 = 0\\{\underline {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, - 3{\rm{b}}\,{{\rm{x}}^2} - 6\,{\rm{b}}\,{\rm{x}} - 9 = 0} _{:\left( { - 3} \right)}}\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{b}}\,{{\rm{x}}^2} + 2\,{\rm{b}}\,{\rm{x}} + 3 = 0\end{array}\)
Syarat paling banyak 1 akar syaratnya :
\(\begin{array}{l}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{D}}\,\, \le \,\,0\\\,\,\,\,\,\,\,\,\,\,\,{{\rm{b}}^2} - 4{\rm{ac}}\,\, \le 0\\4{{\rm{b}}^2} - 4\left( {\rm{b}} \right)\left( 3 \right) \le 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{{\rm{b}}^2} - 3{\rm{b}} \le 0\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm{b}}\left( {{\rm{b}} - 3} \right) \le 0\end{array}\)
\({\rm{a}} \le {\rm{b}} \le 3\)
💥Kunci Jawaban:
💦 Soal No.15
Pembahasan:
L (a) = luas daerah yang dibatasi oleh sumbu -x dan parabola \(y = {x^2} + ax\) dimana 0<a<2
maka peluang nilai a sehingga \({\textstyle{1 \over {48}}} \le {\rm{L}}\left( {\rm{a}} \right) \le {\textstyle{9 \over {16}}}\)
💥Kunci Jawaban: