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\begin{aligned} &\begin{array} {l|l} {\mathrm{x}} & \mathrm{f}(\mathrm{x}) \\ \hline 2.9 & 6.82 \\ 2.9997 & 6.9994 \\ 2.999993 & 6.999986 \\ 2.9999999 & 6.9999998 \end{array} \\ &\begin{array}{ll} & \quad \downarrow & \qquad \qquad \quad \downarrow \\ & \quad 3 & \qquad \qquad \quad 7 \end{array}\end{aligned}