(f) Does the sequence x(2n-1) converge? Estimate its limit.

The graph shows the sequence does not converges only at x=1 because we set x(1) = 1. Elsewhere the graph does not converge. The limit of \(x(n)\) is from 1 to \(\infty\) as \(n\geq 1\) goes to \(\infty\).

(g) Does the sequence x(2n) converge? Estimate its limit.

The graph shows the sequence does not converge only at x(n)=1 because we set x(1) = 1. Elsewhere the graph does not converge. The limit of \(x(n)\) is from 1 to \(\infty\) as \(n\geq 1\) goes to \(\infty\).

(h) Do you think the sequence x(n) converges? If so, why, and if not, why not?

The sequence x(n) does converge at an estimated value of \(x(n) = 1\frac{2}{3}\). I think this because as n increases to \(\infty\) the values of x(n) get closer to the value \(1\frac{2}{3}\). If we look at the graph it becomes more horizontal close to a straight line at \(x(n) = 1\frac{2}{3}\).

(i) Prove, by induction, that \(\vert x(n+1)-x(n)\vert = \frac{1}{2^{n-1}}\) for all \(n\geq 2\).

\[\vert x(n+1)-x(n)\vert = \frac{1}{2^{n-1}}\]

\(x = 0\) \(\rightarrow\) \(\vert x_{2} - x_{1} \vert\) \(\rightarrow\) \(\vert 2-1 \vert\) \(\rightarrow\) 1 = \(\frac{1}{2^0} \)
\(x = 1\) \(\rightarrow\) \(\vert x_{3} - x_{2} \vert\) \(\rightarrow\) \(\frac{1}{2}\vert x_{2} - x_{1} \vert\) \(\rightarrow\) \(\frac{1}{2}\) = \(\frac{1}{2^1}\)
\(x = 2\) \(\rightarrow\) \(\vert x_{4} - x_{3} \vert\) \(\rightarrow\) \( \frac{1}{2} \vert x_{3} - x_{2} \vert\) \(\rightarrow\) \(\frac{1}{4}\) = \(\frac{1}{2^2}\)
\(x = 3\) \(\rightarrow\) \(\vert x_{5} - x_{4} \vert\) \(\rightarrow\) \( \frac{1}{2} \vert x_{4} - x_{3} \vert\) \(\rightarrow\) \(\frac{1}{8}\) = \(\frac{1}{2^3}\)

(j) Use (i) to show that x(n) is a Cauchy sequence.

Cauchy sequence
[x_1, x_2 , x_3, x_4 , ...x_i]
\(\vert x_{n+p} - x_{n} \vert\) for \(p \geq 1\)

x_n is a Cauchy sequence if for all \(\epsilon \geq 0\) there is an N such that. \[x_{n+p} - x_{n} < \epsilon\] where \(n \geq N\) and \(p \geq 1\)

\[\vert x(n+1)-x(n)\vert = \frac{1}{2^{n-1}}\]

\[\frac{1}{2^{n+p-2}} + \frac{1}{2^{n+p-3}} + \dots + \frac{1}{2^{n-1}}\] \[\frac{1}{2^{n-1}} (\frac{1}{2^{p-1}} + \frac{1}{2^{p-2}} + \dots + 1)\]