pt$\Leftrightarrow$$\sqrt{(x+\frac{1}{2})^{2}+\frac{3}{4}}$-$\sqrt{(x-1)^{2}+1}$=mĐặt $\overrightarrow{u}$(x+$\frac{1}{2}$;$\frac{\sqrt{3}}{2}$);$\overrightarrow{v}$(x-1;1) Ta có:$\left| {\left| {\overrightarrow{u}} \right|-\left| {\overrightarrow{v}} \right|} \right|$$\leq$$\left| {\overrightarrow{u}-\overrightarrow{v}} \right|$$\Rightarrow$$\left| {m} \right|$$\leq$$\sqrt{4-\sqrt{3}}$$\Leftrightarrow$-$\sqrt{4-\sqrt{3}}$$\leq$m$\leq$$\sqrt{4-\sqrt{3}}$
pt$\Leftrightarrow$$\sqrt{(x+\frac{1}{2})^{2}+\frac{3}{4}}$-$\sqrt{(x-1)^{2}+1}$=mĐặt $\overrightarrow{u}$(x+$\frac{1}{2}$;$\frac{\sqrt{3}}{2}$);$\overrightarrow{v}$(x-1;1) Ta có:$\left| {\left| {\overrightarrow{u}} \right|-\left| {\overrightarrow{v}} \right|} \right|$$\leq$$\left| {\overrightarrow{u}$\overrightarrow{v}} \right|$$\Rightarrow$$\left| {m} \right|$$\leq$$\sqrt{4-\sqrt{3}}$$\Leftrightarrow$-$\sqrt{4-\sqrt{3}}$$\leq$m$\leq$$\sqrt{4-\sqrt{3}}$
pt$\Leftrightarrow$$\sqrt{(x+\frac{1}{2})^{2}+\frac{3}{4}}$-$\sqrt{(x-1)^{2}+1}$=mĐặt $\overrightarrow{u}$(x+$\frac{1}{2}$;$\frac{\sqrt{3}}{2}$);$\overrightarrow{v}$(x-1;1) Ta có:$\left| {\left| {\overrightarrow{u}} \right|-\left| {\overrightarrow{v}} \right|} \right|$$\leq$$\left| {\overrightarrow{u}
-\overrightarrow{v}} \right|$$\Rightarrow$$\left| {m} \right|$$\leq$$\sqrt{4-\sqrt{3}}$$\Leftrightarrow$-$\sqrt{4-\sqrt{3}}$$\leq$m$\leq$$\sqrt{4-\sqrt{3}}$