What is the sum of series is numbers 64&66 ?
Using the summation notation
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Answer:
64. 6138
66. 8.078125
Step-by-step explanation:
Let's take it one number at a time.
For number 64:
[tex]6(2)^{1-1}=6[/tex]
[tex]6(2)^{2-1}=12[/tex]
[tex]6(2)^{3-1}=24[/tex]
[tex]6(2)^{4-1}=48[/tex]
[tex]6(2)^{5-1}=96[/tex]
[tex]6(2)^{6-1}=192[/tex]
[tex]6(2)^{7-1}=384[/tex]
[tex]6(2)^{8-1}=768[/tex]
[tex]6(2)^{9-1}=1536[/tex]
[tex]6(2)^{10-1}=3072[/tex]
Sum = 6 + 12 + 24 + 48 + 96 + 192 + 384 + 768 + 1536 + 3072
Sum = 6138
For number 66:
[tex]12(-\frac{1}{2})^{0}=12[/tex]
[tex]12(-\frac{1}{2})^{1}=-6[/tex]
[tex]12(-\frac{1}{2})^{2}=3[/tex]
[tex]12(-\frac{1}{2})^{3}=-1.5[/tex]
[tex]12(-\frac{1}{2})^{4}=0.75[/tex]
[tex]12(-\frac{1}{2})^{5}=-0.375[/tex]
[tex]12(-\frac{1}{2})^{6}=0.1875[/tex]
[tex]12(-\frac{1}{2})^{7}=-0.0078125[/tex]
[tex]12(-\frac{1}{2})^{8}=0.046875[/tex]
[tex]12(-\frac{1}{2})^{9}=-0.0234375[/tex]
Sum = 12 + -6 + 3 + -1.5 + 0.75 + -0.375 + 0.1875 + -0.0078125 + 0.046875 + -0.0234375
or to make things simpler:
Sum = 12 - 6 + 3 - 1.5 + 0.75 - 0.375 + 0.1875 - 0.0078125 + 0.046875 - 0.0234375
Sum = 8.078125