Soal dan Pembahasan Matematika Dasar SNMPTN 2009 (Kode 383)
-Matematika Dasar -
- (A) -5 < |5x - 5|
- (B) |x - 1| < 1
- (C) 5x - 5 > -5
- (D) 5x - 5 > -5
- (E) 0 < 5 - 5x < 5
Penyelesian : \(\begin{array}{l}15 - 5x| < 5 \to - \,5 < 5 - 5x < 5\\{\rm{ }} - 1 < 1 - x < 1 \Rightarrow \left| {x - 1} \right| < 1\end{array}\)
Kunci Jawaban: B
- (A) \(\frac{{a + b}}{{a - b}}\)
- (B) c
- (C) \(\frac{{a - b}}{{a + b}}\)
- (D) \(\frac{1}{c}\)
- (E) 1
Penyelesian : \(\frac{{{x^2} - bx}}{{ax - c}} = \frac{{m - 1}}{{m + 1}}\) \(\begin{array}{l}\left( {m + 1} \right)\left( {{x^2} - bx} \right) = \left( {m - 1} \right)\left( {ax - c} \right)\\\left( {m + 1} \right){x^2} - \left\{ {m\,(a + b) + (b - a)} \right\}x + c\,(m - 1) = 0 \to {x_1} = - {x_2}\\{x_1} + {x_2} = 0\,\,\,\,\,\,\,\, \to \,\,\,\,\,{x_1} + {x_2} = \frac{{ - B}}{A} = 0\\\frac{{m(a + b) + (b - a)}}{{m + 1}} = 0\,\,\,\,\,\,\,\, \Rightarrow \,\,\,\begin{array}{*{20}{c}}{m\,(a + b) + (b - a) = 0}\\{m\,(a + b) = a - b}\\{m = \frac{{a - b}}{{a + b}}}\end{array}\end{array}\)
Kunci Jawaban: C
- (A) 1:7
- (B) 1:16
- (C) 1:45
- (D) 1:49
- (E) 1:64
- (A) \(\frac{3}{{25}}\)
- (B) \(\frac{7}{{50}}\)
- (C) \(\frac{4}{{25}}\)
- (D) \(\frac{9}{{50}}\)
- (E) \(\frac{2}{{5}}\)
1) Nomor Bola : 1, 2, 3, 4 ..., 100 = 100 bola
2) Nomor Bola habis dibagi 5 \( = \left\{ {{B_5},\,\,{B_{10}},\,\,{B_{15}},\,\,...,\,\,{B_{100}}} \right\}\) \({{\rm{n}}_{\rm{1}}} = 20\) bola
3) Nomor bola habis dibagi 9 dan 3 \( = \left\{ {{B_{15}},\,\,{B_{30}},\,\,{B_{45}},{B_{60}},\,\,{B_{75}},\,\,{B_{90}}} \right\}\) \({{\rm{n}}_{\rm{2}}} = 6\) bola
4) Nomor bola habis di bagi 5 dan tidak habis dibagi 3 \({\rm{ = }}{{\rm{n}}_{\rm{1}}} - {{\rm{n}}_{\rm{2}}} = 20 - 6 = 14\)
5) Peluang \( = \frac{{14}}{{100}} = \frac{7}{{50}}\)
Kunci Jawaban: B
- (A) \(\left( {\begin{array}{*{20}{c}}2&3\\3&5\end{array}} \right)\)
- (B) \(\left( {\begin{array}{*{20}{c}}0&7\\7&0\end{array}} \right)\)
- (C) \(\left( {\begin{array}{*{20}{c}}0&{ - 7}\\{ - 7}&0\end{array}} \right)\)
- (D) \(\left( {\begin{array}{*{20}{c}}7&0\\0&7\end{array}} \right)\)
- (E) \(\left( {\begin{array}{*{20}{c}}7&7\\0&0\end{array}} \right)\)
Diketahui : \(A = \left[ {\begin{array}{*{20}{c}}3&2\\4&1\end{array}} \right];\,\,\,\,\,B = \left[ {\begin{array}{*{20}{c}}1&{ - 4}\\{ - 2}&3\end{array}} \right]\)
miss : \(A = \left[ {\begin{array}{*{20}{c}}a&b\\c&d\end{array}} \right] \Rightarrow B = \left[ {\begin{array}{*{20}{c}}d&c\\{ - b}&a\end{array}} \right]\)
\(\,\,C = \left[ {\begin{array}{*{20}{c}}5&{ - 3}\\{ - 3}&2\end{array}} \right] \Rightarrow D = \left[ {\begin{array}{*{20}{c}}2&3\\3&5\end{array}} \right]\)
Jadi matrik : C + D \( = \left[ {\begin{array}{*{20}{c}}5&{ - 3}\\{ - 3}&2\end{array}} \right] + \left[ {\begin{array}{*{20}{c}}2&3\\3&5\end{array}} \right] = \left[ {\begin{array}{*{20}{c}}7&0\\0&7\end{array}} \right]\)
Kunci Jawaban: D
- (A) kanan sumbu X sejauh 2 satuan dan ke arah bawah sumbu Y sejauh 3 satuan
- (B) kiri sumbu X sejauh 3 satuan dan ke arah atas sumbu Y sejauh 2 satuan
- (C) kanan sumbu X sejauh 3 satuan dan ke arah bawah sumbu Y sejauh 2 satuan
- (D) kanan sumbu X sejauh 6 satuan dan ke arah bawah sumbu Y sejauh 7 satuan
- (E) kiri sumbu X sejauh 2 satuan dan ke arah atas sumbu Y sejauh 3 satuan
Penyelesaian : \(f(x) = x2 - 6x + 7 = x2 - 6x + 9 - 2 = {(x - 3)^2} - 2\)
Dapat diperoleh dengan cara menggeser grafik fungsi \(f\left( x \right) = {x^2}\) ke arah - Kanan Sumbu x sejauh 3 satuan dan ke arah bawah Sumbu Y sejauh 2 satuan.
Kunci Jawaban: C
- (A) (~ P \( \vee \) Q) \( \wedge \) R
- (B) (~ Q \( \vee \) ~ R) \( \wedge \) (~ Q \( \vee \) P)
- (C) (P \( \wedge \) ~Q) \( \wedge \) (Q \( \vee \) ~ R)
- (D) ~ P \( \Rightarrow \) R
- (E) ~ R \( \wedge \) ~ (Q \( \wedge \) R)
Kunci Jawaban: E
- (A) \(\left\{ \begin{array}{l}x + 4 = 2y\\x - 7 = 3y\end{array} \right.\)
- (B) \(\left\{ \begin{array}{l}x - 4 = 3y\\x + 7 = 2y\end{array} \right.\)
- (C) \(\left\{ \begin{array}{l}x - 4 = 3y\\x + 7 = y\end{array} \right.\)
- (D) \(\left\{ \begin{array}{l}x + 4 = y\\x - 7 = 2y\end{array} \right.\)
- (E) \(\left\{ \begin{array}{l}x - 4 = 2y\\x + 7 = 3y\end{array} \right.\)
- Jika tiap anak di beri 2 permen, maka di dalam kantong masih tersisa 4 permen :
- x = 2y + 4 atau x - 4 = 2y
- Jika tiap anak diberi 5 permen akan ada 2 anak yang tidak mendapat permen dan 1 anak mendapat 2 permen
Kunci Jawaban: E
- (A) 240
- (B) 120
- (C) 80
- (D) 60
- (E) 30
Penyelesian : Tunggal \(_5{C_2} = 10\)
Ganda (non tunggal) \(_3{C_2} = 3\)
Ganda (tunggal sekali) \(_2{C_1} = 2\)
10 . 3 . 2 = 60
Kunci Jawaban: D
- (A) 40
- (B) 22,5
- (C) 21,5
- (D) 20
- (E) 8
\(\frac{\begin{array}{l}px + 2y = 8\,\,\,\,\,\,\,\,\,\,\,\,1)\\3x - qy = 38\,\,\,\,\,\,\,\,\,2)\end{array}}{\begin{array}{l}\\(p + 3) + = 46\,\,\,\,\,\,\, \to \end{array}} + \)
Kunci Jawaban: D
- (A) tak terhingga
- (B) 36 km
- (C) 32 km
- (D) 26 km
- (E) 18 km
Penyelesaian : Jarak tempuh orang dalam km merupakan deret geometri tak hingga keuangan dengan :
\(12 + 4 + \frac{4}{3} + \,...\, = \frac{{12}}{{1 - \frac{1}{3}}} = 18\,\,km\)
Kunci Jawaban: E
- (A) 4
- (B) 5
- (C) 8
- (D) 10
- (E) 13
Penyelesaian :
\(f(x) = 7 - \sqrt {25 - {x^2}} \)
- Titik stasioner f'(x)=0
- \(b = f(a) = f(0) = 7 - \sqrt {25 - {0^2}} = 2\)
- Jadi \({a^2} + {b^2} = {0^2} + {2^2} = 4\)
- (A) 99
- (B) 90
- (C) 81
- (D) 72
- (E) 63
Penyesaian :
\({U_1} + {U_2} + {U_3}\,...\, + {U_{101}} = 18180 \to \) deret aritmatika
\(\begin{array}{l}U{}_1,\,\,b = 3,\,\,{S_{101}} = 18180\\\frac{{101}}{2}(2\,\,.\,\,{U_1} + (101 - 1)3) = 18180\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{U_1} + 150 = 180\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{U_1} = 130\end{array}\)
Jadi \({U_1} + {U_2} + {U_3} = 30 + 33 + 36 = 99\)
Kunci Jawaban: A
- (A) \(\frac{{2101}}{{625}}\) Juta surat
- (B) \(\frac{{369}}{{125}}\) Juta surat
- (C) \(\frac{{2100}}{{625}}\) Juta surat
- (D) \(\frac{{365}}{{125}}\) Juta surat
- (E) \(\frac{{360}}{{125}}\) Juta surat
Penyelesaian :
\({S_n} = \frac{{a(1 - {r^n})}}{{1 - r}} \Rightarrow {S_5} = \frac{{1\left( {1 - {{\left( {\frac{4}{5}} \right)}^5}} \right)}}{{1 - \frac{4}{5}}}\)
\(S5 = \frac{{2101}}{{625}}{\rm{ }}\) juta surat
Kunci Jawaban: A
- (A) 36
- (B) 54
- (C) 72
- (D) 90
- (E) 108
Penyelesaian :
Ketua Sekretaris Anggota
\(\begin{array}{l}{\rm{ 3 }} \times {\rm{ 3 }} \times {\rm{ C}}_2^4\\ = 3 \times 3 \times 6 = 54\end{array}\)
Kunci Jawaban: B