PERTEMUAN 7
1.
1 1 1
− −
2 4 8 = ...
1 1
−
6 12
1 1 1 4 − 2 −1
1
− −
12 3
2 4 8 =
8
= 8 =
=
1 1
2 −1
1
8
2
−
6 12
12
12
2. 2m − 5n − 1 m + 2 n = ...
5
3
1
2
m+ n
5
3
1  
2 

=  2m − m  −  5n − n 
5  
3 

10 − 1
15 − 2
=
m−
n
5
3
9
13
= m−
n
5
3
2m − 5n −
3.
4.
5
n
7
= ...
1
4n +
n
14
9
 14 − 5 
5
2n − n

n
7
 = 7
7 =
1
57
56 + 1 

4n +
n 
n
2

14
 14 
14
9
18
6
=
=
=
57 57 19
2
9
n
11  14  1  49 = ...
12
1
196
n
121
7
2n −
3
9
n
11
4
5.

14
1

 49
1
196
7
12
n
12111
3
1
=
 14  7 
7
4
14
11
33
1617
=
 49 =
4
4
11 12 5
9
+
+
+
= ...
44 48 20 36
11 12 5
9 1 1 1 1
1
+
+
+
= + + + = 4  = 1
44 48 20 36 4 4 4 4
4
6.
y
x +y
= ...
x −y
x +y
x+
x 2 + xy + y
y
x +y
x 2 + xy + y
x +y
=
=
x −y
x −y
x −y
x +y
x +y
x+
7.
8.
1 1 3 7 1
: +  +
6 3 2 6 4 = ...
1
24
1 1 3 7 1 1 3+ 3  7 + 1
: +  +
2 62 4
6 3 2 6 4 = 6
1
1
24
24
1 7 1 2 + 7 +1
+ +
10
4
= 2 4 4 =
=
= 10  6 = 60
1
1
1
24
6
24 6
0,875 0,25

: 0,6 = ...
0,625 0,75
7 1
0,875 0,25 6
8
4 5

:
=


3 3
0,625 0,75 10 5
8
4
=
7 1 5 7
 
=
5 3 3 9
1
3
x− x
9.
4
4 = ...
1
2
 4 +1− 3 
1
3
x+ x− x 
x
4
4 =  42  = 2 x = x
1
1
2
2
2
1
y−
y −1
10.
= ...
1
y −1
x+
1
y2 − y −1
y −1
y −1
=
= y2 − y −1
1
1
y −1
y −1
y−
x = 0,375%  5,43
141. y = 5,43%  0,375
x = y(C )
x=p
y = p+2
p = −2
142.
x = −2
y =0
x  y(B)
2 x = 26
x =6
143. 3y = 34
y =4
x  y(A)
xz
144. x  y  z
x  y(A)
x = negatif
145. y = positif
x  y(B)
x=y
3p − 5 = 2p2 + 4
2
p2 − 9 = 0
146. (p − 3)(p + 3) = 0
p=3
p = −3
(E )
x = 64 = 8
64
153. y =
= 16
4
x  y(B)
x = positif
154. y = negatif
x  y(A)
x = 2 + 4 + 6 + ... + 48 = n(n + 1) = 24.25
48 = 2n
n = 24
155.
y = 1 + 3 + 5 + ... + 49 = n2 = 25.25
49 = 2n − 1
50 = 2n
n = 25
x  y(B)