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            • 1.
              圆\(x^{2}+y^{2}-2x-1=0\)关于直线\(2x-y+3=0\)对称的圆的方程是\((\)  \()\)
              A.\((x+3)^{2}+(y-2)^{2}= \dfrac {1}{2}\)
              B.\((x-3)^{2}+(y+2)^{2}= \dfrac {1}{2}\)
              C.\((x+3)^{2}+(y-2)^{2}=2\)
              D.\((x-3)^{2}+(y+2)^{2}=2\)
            • 2.

              \(( 1 )\)已知向量\(\overrightarrow{a},\overrightarrow{b}\),满足\(\overrightarrow{a}=\left( 1,3 \right)\),\(\left( \overrightarrow{a}+\overrightarrow{b} \right)\bot \left( \overrightarrow{a}-\overrightarrow{b} \right)\),则\(\left| \overrightarrow{b} \right|=\)______.

              \(( 2 )\)已知实数\(x,y\)满足\(\begin{cases} & x\leqslant 3 \\ & x+y-3\geqslant 0 \\ & x-y+1\geqslant 0 \\ \end{cases}\),则\({{x}^{2}}+{{y}^{2}}\)的最小值是     

              \(( 3 )\)已知圆\(O:{{x}^{2}}+{{y}^{2}}=1.\)圆\({O}{{'}}\)与圆\(O\)关于直线\(x+y-2=0\)对称,则圆\({O}{{'}}\)的方程是__________.

              \(( 4 )\)已知数列\(\left\{ a{}_{n} \right\},\left\{ {{b}_{n}} \right\}\)满足\(b{}_{n}=\log {}_{2}a{}_{n},n\in {{N}^{*}}\),其中\(\left\{ {{b}_{n}} \right\}\)是等差数列,且\({{a}_{9}}{{a}_{2009}}=\dfrac{1}{4}.\)则\({{b}_{1}}+{{b}_{2}}+{{b}_{3}}+\cdot \cdot \cdot +{{b}_{2017}}=\)__________.

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