323
Halaman 1
PEMBAHASAN SELEKSI NASIONAL MASUK PERGURUAN TINGGI NEGERI (SNMPTN)
Mata Pelajaran : Matematika Dasar
Tanggal
: 12 Juni 2012
Kode Soal
: 323
1. Jawab: D
Eksponen
20 19 19 19
20 2 2 2 1 2
b
a = − = − =
2
a = b=19
21
a+b=
2. Jawab: A
Sistem Persamaan Linear
2 3
2 5
2 7
3 3 3 15
5
x y
y z
z x
x y z
x y z
+ =
+ =
+ = +
+ + =
+ + =
3. Jawab: D
Persamaan Kuadrat
1 1
x =p− x2 =p+1
2
4 0
x − x+a=
1 2
b
x x
a
+ = −
2p=4→ p=2
1 1
x = x2 =3
1 2 x x =a
1 3⋅ =a→a =3
4. Jawab: B
Logaritma
3 2
2 3 9
a= →a= =
(
2)(
)
2a
a b =
2 2
2 2 4
b= →b= =
13
a+b=
5. Jawab: E
Fungsi Kuadrat
Puncak
(
α β)
→y−β =a x(
−α)
2 Puncak(
2 −1)
y+ =1 a x(
−2)
2 Melalui(
0 −5)
− + =5 1 a(
0−2)
24 4a
− =
1
a= −
(
)
21 1 2
y+ = − x−
(
2)
1 4 4
y+ = − x − x+
2
4 5
y= −x + x−
2
4 5
f x = −x + x−
5 25 20 5 10
f = − + − = −
6. Jawab: E
Matriks
1 2 1 1
1 5 3 2
a b
c d =
1 1 5 2
1
1 5 2 1 3 2 1 1
a b
c d
− =
⋅ − ⋅ −
5 1 2 1
1
3 15 2 6 2
− − +
=
− − +
4 1
3 3
13 4
3 3
− =
−
4 1 13 4
4
3 3 3 3
a+ + +b c d = − + − =
7. Jawab: A
Statistika
7 19
k
f = fk8 =22 fk =25
8 7 100 3 100
25 k k
k
f f
f
−
⋅ = ⋅
323
Halaman 2 8. Jawab: C
Deret Aritmatika
1001
a =
997 1001 4
b = − = −
0 n
U <
(
1)
0a+ n− b<
(
)( )
1001+ n−1 −4 <0 1001−4n+4<0
4n 1005
− < −
4n>1005
1 4
251
n >
252
n =
9. Jawab: E
Fungsi
2
f x = x+b
( )
19 3
f− =
maka f(3) = 3 6 + b = 9
b = 3
2 3
f x = x+
(
3)
( )
9 21f f = f =
10. Jawab: D
Program Linear
(
)
3 4f x y = x+ y
(
3 6)
9 24 33f = + =
(
6 4)
18 16 34f = + =
33
f =
11. Jawab: B
Statistika
1 9
n = x1 =61
2 1
n = x2 =
63 5
x =
1 2
1 2
1 2
n x n x
x
n n
+ =
+
2
9 61 63 5
10
x
⋅ +
=
2
635=549+x
2 86
x =
12. Jawab: D
Aritmetika Sosial
Sewa = 15.000.000 Banyak barang = 3.000 Bahan baku = 2.000
Biaya bahan baku total = 3.000 x 2.000 = 6.000.000 Modal = biaya + bahan baku = 15.000.000 + 6.000.000 = 21.000.000
Harga penjualan minimum agar tidak rugi 21 000 000
7 000 3 000
= =
13. Jawab: A
Deret Geometri
(
1)
3 2 2 n nS = − −
(
0)
1 3 2 2 3
a= S = − =
1 1
2 2
r = − =
2 3 1 4
a+ r= + =
3 6
12 4
8
323
Halaman 3 14. Jawab: B
Bidang Datar
1 5 L=
1 1
5 5
xy y
x
= → =
2y =1
2 2
1
5x = →x = 5
15. Jawab: C
Pertidaksamaan
(
x+5)(
x−3)
< x−32
2 15 3
x + x− < x−
2
12 0
x +x− <
(
x+4)(
x−3)
<04 x 3
− < <
−4 3
− +