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1952 AMC 12 Question 50

AMC12 · 1952 AMC 12

Question 50

A line initially $1$ inch long grows according to the following law, where the first term is the initial length. $$
\begin{gathered} 1+\frac14\sqrt2+\frac14+\frac1{16}\sqrt2\\ {}+\frac1{16}+\frac1{64}\sqrt2+\frac1{64}+\cdots. \end{gathered}
$$ If the growth process continues forever, the limit of the length of the line is:
  1. $\infty$
  2. $\dfrac43$
  3. $\dfrac38$
  4. $\dfrac13(4+\sqrt2)$
  5. $\dfrac23(4+\sqrt2)$