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\begin{aligned} &\operatorname{At}(1,1), \mathrm{m}_{\tan }=\lim\limits_{h \rightarrow 0} \frac{f(1+h)-f(1)}{(1+h)-(1)}=\lim\limits_{h \rightarrow 0} \frac{(1+h)^{2}-(1)^{2}}{h}=\lim\limits_{h \rightarrow 0} \frac{\left\{1+2 h+h^{2}\right\}-1}{h} \\ &=\lim\limits_{h \rightarrow 0} \frac{2 h+h^{2}}{h}=\lim\limits_{h \rightarrow 0} \frac{h(1+h)}{h}=\lim\limits_{h \rightarrow 0}(2+h)=2 \end{aligned}