SOLUTION: What is the continues pattern for these numbers. 3, -6, 12, 4, 20, ?

Algebra ->  Sequences-and-series -> SOLUTION: What is the continues pattern for these numbers. 3, -6, 12, 4, 20, ?      Log On


   

Question 1126579: What is the continues pattern for these numbers. 3, -6, 12, 4, 20, ?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Arithmetic Sequence
definition of nth term: a%5Bn%5D+=+a%5B1%5D+%2B+d+%28n-1%29
3,....-6,....12,.....4,.....20,-----------------213
-- -9.....18.....-8.....16--------------------193
........27.....-26....24----------------------177
........... -53.....50------------------------153
............. 103--------------------------103
Differences didn't converge, there is no+common+difference; so, it is not Arithmetic Sequence
3,....-6,....12,.....4,.....20
Geometric Sequence
definition of nth term: +a%5Bn%5D=+a%5B1%5D%2Ar%5E%28n-1%29
find out if there is common ratio:
a%5B1%5D=3 and a%5B2%5D=-6
a%5B2%5D=+a%5B1%5D%2A+r%5E%282-1%29
a%5B2%5D%2Fa%5B1%5D=r
r=-6%2F3
r=-2
check second and third term
a%5B2%5D=-6 and a%5B3%5D=12
a%5B3%5D%2F+a%5B2%5D=+r%5E%283-1%29
12%2F+-6=+r%5E2
-2=+r%5E2
r=sqrt%28-2%29
since not equal, there is no+common+ratio
since your sequence is neither arithmetic nor geometric sequence, there is no way to find next term