Can you explain how to find explicit and recursive formula of geometric sequence given 2 terms?
23. a<4> = -12, a<5> = -6
ratio: -6/-12 = 1/2
explicit:
a<n> = ar^(n-1)
-6 = a(1/2)^4
-6 = a(0.37)
-0.010 = a???
a<n> = -0.010(1/2)^n-1
recursive:
a<n> = a<n-1>r
a<n> = -0.010(1/2) ???
find 8th term:
a<n>=ar^n-1
a<8> = -0.010(1/2)^7
a<8> = -0.010(.0078125)
a<8> =-0.00078125
24. a<5>=738, a<2>= 12
ratio: 738/12 = 256/8 = 32 (I divided by 8 because 3 terms skipped. 2^3 = 8. How do i know the correct number to divide by? if terms aren't consecutive?)
explicit:
a<n> = ar^(n-1)
12 = a(32)^1
12 = 32a
0.375=a
a<n>= 0.375(32)^n-1
recursive:
a<n> = a<n-1>r
a<n> = a<n-1>32
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