1a. This is an increasing arithmetic sequence.
2a. r = 0.9r + 30
r = 0.9r + 30
­0.9r ­0.9r
0.1r = 30
0.1
0.1
r = 300
2c.
2d.
t = 0.82t
­0.82t ­0.82t
0.18t = 0
0.18
0.18
t = 0
v = 45 + v
­ v
­ v
45 = 0
This is a false equation since 45 does not equal 0.
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3a.
0.75x + 25 = x
­0.75x
­0.75x
25 = 0.25x
0.25 0.25
x = 100
4b. 100, 160, 226, 298.6, ... is a shifted geometric sequence
which means the "next" term is r times the "previous" term
plus d for any pair of consecutive terms. Thus, .
100 r + d = 160
.
160 r + d = 226
u(n) = 1.1u(n - 1) + 50
u(0) = 100
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