Converging Infinite Series: Examining the Limit of (2^(n)+1)/2^(n+1)

  • Thread starter Thread starter kdinser
  • Start date Start date
AI Thread Summary
The discussion focuses on the convergence of the infinite series defined by the limit of (2^(n)+1)/2^(n+1) as n approaches infinity. It is established that this limit equals 1/2, derived from the expression (1 + 2^(-n))/2. The participants clarify the algebraic manipulation involved, particularly the relationship between 2^(n+1) and 2^n. The conversation highlights the importance of understanding limits in the context of series convergence. Overall, the thread emphasizes resolving confusion around algebraic expressions related to infinite series.
kdinser
Messages
335
Reaction score
2
This is in the series and convergence chapter

infinit sum (2^(n)+1)/2^(n+1)

lim as n goes to infinity of
(2^(n)+1)/2^(n+1) = \frac{1+2^{-n}}{2}=1/2

couldn't get latex to work right for the first part.
 
Last edited:
Physics news on Phys.org
Lim_{n \inf} {(\frac{1}{2})}^n = 0
 
Last edited:
You have:
\frac{2^{n}+1}{2^{n+1}}=\frac{1}{2}\frac{2^{n}+1}{2^{n}}=\frac{1}{2}(1+2^{-n})
 
Last edited:
Thanks, my algebra still seems to be a little rusty.

forgot that 2^{n+1}=2^n * 2^1

makes sense now and so do a few other ones that have been giving me headaches this morning.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top