grandes-ecoles 2020 Q40

grandes-ecoles · France · centrale-maths1__psi Proof Computation of a Limit, Value, or Explicit Formula
Using Table 1 below, give an approximate bound for the value of $m$ and the value of a real number $h > 0$ such that there exists a rank $n_0 \in \mathbb{N}^*$ satisfying for all $n \geqslant n_0$, $$P\left(S_n > 1{,}1 \times nm\right) \leqslant \mathrm{e}^{-nh}.$$
$x_i$4,504,554,604,654,70
$\hat{\lambda}^*(x_i)$$4{,}1 \times 10^{-12}$$4{,}1 \times 10^{-12}$$4{,}1 \times 10^{-12}$$4{,}1 \times 10^{-12}$$4{,}1 \times 10^{-12}$
$x_i$4,754,804,854,904,95
$\hat{\lambda}^*(x_i)$$5{,}1 \times 10^{-4}$$5{,}5 \times 10^{-3}$$1{,}1 \times 10^{-2}$$1{,}6 \times 10^{-2}$$2{,}1 \times 10^{-2}$
$x_i$5,005,055,105,155,20
$\hat{\lambda}^*(x_i)$$2{,}6 \times 10^{-2}$$3{,}1 \times 10^{-2}$$3{,}6 \times 10^{-2}$$4{,}1 \times 10^{-2}$$4{,}6 \times 10^{-2}$
$x_i$5,255,305,355,405,45
$\hat{\lambda}^*(x_i)$$5{,}1 \times 10^{-2}$$5{,}6 \times 10^{-2}$$6{,}1 \times 10^{-2}$$6{,}6 \times 10^{-2}$$7{,}1 \times 10^{-2}$
Using Table 1 below, give an approximate bound for the value of $m$ and the value of a real number $h > 0$ such that there exists a rank $n_0 \in \mathbb{N}^*$ satisfying for all $n \geqslant n_0$,
$$P\left(S_n > 1{,}1 \times nm\right) \leqslant \mathrm{e}^{-nh}.$$

\begin{tabular}{|l|l|l|l|l|l|}
\hline
$x_i$ & 4,50 & 4,55 & 4,60 & 4,65 & 4,70 \\
\hline
$\hat{\lambda}^*(x_i)$ & $4{,}1 \times 10^{-12}$ & $4{,}1 \times 10^{-12}$ & $4{,}1 \times 10^{-12}$ & $4{,}1 \times 10^{-12}$ & $4{,}1 \times 10^{-12}$ \\
\hline
$x_i$ & 4,75 & 4,80 & 4,85 & 4,90 & 4,95 \\
\hline
$\hat{\lambda}^*(x_i)$ & $5{,}1 \times 10^{-4}$ & $5{,}5 \times 10^{-3}$ & $1{,}1 \times 10^{-2}$ & $1{,}6 \times 10^{-2}$ & $2{,}1 \times 10^{-2}$ \\
\hline
$x_i$ & 5,00 & 5,05 & 5,10 & 5,15 & 5,20 \\
\hline
$\hat{\lambda}^*(x_i)$ & $2{,}6 \times 10^{-2}$ & $3{,}1 \times 10^{-2}$ & $3{,}6 \times 10^{-2}$ & $4{,}1 \times 10^{-2}$ & $4{,}6 \times 10^{-2}$ \\
\hline
$x_i$ & 5,25 & 5,30 & 5,35 & 5,40 & 5,45 \\
\hline
$\hat{\lambda}^*(x_i)$ & $5{,}1 \times 10^{-2}$ & $5{,}6 \times 10^{-2}$ & $6{,}1 \times 10^{-2}$ & $6{,}6 \times 10^{-2}$ & $7{,}1 \times 10^{-2}$ \\
\hline
\end{tabular}