Question

What is the tenth term of the geometric series if the first, second and third terms are 0.5, 1.0, 2.0, ... ?

Answer 1

please help

Answer 2

\[r=a_{2}/a_{1}=1/0.5=2\]

Answer 3

You are starting at 0.5, and each time, you double what you had before. Just keep doubling until you get to the 10th term.

Answer 4

the series can be written as An = 2*(An-1) or .5*2^n-1
so A10 = .5*2^9 = 256

Answer 5

\[a_{10}=a _{1}*r^{9}=0.5*2^9=2^8=256\]

Answer 6

its result is 512

Answer 7

0.5 time 2^10= 2^9 = 512? 0r how?

Answer 8

Result should be 512

Answer 9

Oh, whoops. Should be 256. It's only multiplied 9 times. 0.5*2^9

Answer 10

its \[0.5*2^{n-1} = 0.5*2^{10-1} = 0.5*2^{9} = 256\]

Answer 11

Formula \[a_{n}=a _{1}*r^{n-1}\]

Answer 12

but its result is 512