によって dian causin 6年前.
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                        Geometric Sequence,Means, and Infinite Geometric Sequence
                        
                        
                             
                            
                         
                     
                 
             
            
                
                    
                    Geometric Sequence,Means, and Infinite Geometric Sequence
Labels:
d=Distance
r=Common Ratio
n=The Number of Terms
an=The nth term
a1=First Term
Geometric Means
Example:
1.)2,10,50,250,1250
r=?                   n=5
an=1250           a1=2
Sn=1250=2r
1250=2r
1250=2r
  2      2
625=r
5=r=Final Answer
Infinite Geometric Sequence
Sum of an Infinite Geometric Sequence
Example:
2, 6, 18,...
3 15 75
r=3   a1=2
   5        3
S= 2
     3
   1-3
      5
S=5
    3
Formula:
s=a1
     1-r
Divergent=|r|>1
Convergent=|r|<1
Example:
3,6,12,24,...,S10
n=10          r=2
a1=3
S10=3(1-2 )
        1-2
     =3(-1024)
            -1
 S10=3069=Final Answer
Formula:
Sn=a1(1-r )
        1-r      r=1
Sn=a1-an
           1-r       r=1
Geometric Sequence
Example:
1.)4,8,16,32,...,a12
a1=4              r=4
n=12            an=12
a12=4(2)
a12=4(2 )
a12=2048=Final Answer
Formula:
an=a1(r)
What is Geometric Sequence
-A sequence in which each term after the first term is obtained by multiplying.