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            • 1.
              如图,数轴上点\(A\)表示的数为\(a\),化简:\(a+ \sqrt {a^{2}-4a+4}=\) ______ .
            • 2.
              先化简,再求值:\(a(a+2b)-(a+1)^{2}+2a\),其中\(a= \sqrt {2}+1,b= \sqrt {2}-1\).
            • 3.
              计算\(( \sqrt {3}+ \sqrt {2})- \sqrt {3}\)的结果是 ______
            • 4.
              先化简,再求值:\((x+y)(x-y)+y(x+2y)-(x-y)^{2}\),其中\(x=2+ \sqrt {3}\),\(y=2- \sqrt {3}\).
            • 5. 下列二次根式中能与\(2 \sqrt {3}\)合并的是\((\)  \()\)
              A.\( \sqrt {8}\)
              B.\( \sqrt { \dfrac {1}{3}}\)
              C.\( \sqrt {18}\)
              D.\( \sqrt {9}\)
            • 6. 化简\( \sqrt {(-2)^{2}}\)的结果是\((\)  \()\)
              A.\(-2\)
              B.\(±2\)
              C.\(2\)
              D.\(4\)
            • 7. 观察下列各式:
              \( \sqrt {1+ \dfrac {1}{1^{2}}+ \dfrac {1}{2^{2}}}=1+ \dfrac {1}{1\times 2}\),
              \( \sqrt {1+ \dfrac {1}{2^{2}}+ \dfrac {1}{3^{2}}}=1+ \dfrac {1}{2\times 3}\),
              \( \sqrt {1+ \dfrac {1}{3^{2}}+ \dfrac {1}{4^{2}}}=1+ \dfrac {1}{3\times 4}\),
              \(……\)
              请利用你所发现的规律,
              计算\( \sqrt {1+ \dfrac {1}{1^{2}}+ \dfrac {1}{2^{2}}}+ \sqrt {1+ \dfrac {1}{2^{2}}+ \dfrac {1}{3^{2}}}+ \sqrt {1+ \dfrac {1}{3^{2}}+ \dfrac {1}{4^{2}}}+…+ \sqrt {1+ \dfrac {1}{9^{2}}+ \dfrac {1}{10^{2}}}\),其结果为______.
            • 8. 下列各式计算正确的是\((\)  \()\)
              A.\(a^{12}÷a^{6}=a^{2}\)
              B.\((x+y)^{2}=x^{2}+y^{2}\)
              C.\( \dfrac {x-2}{4-x^{2}}= \dfrac {1}{2+x}\)
              D.\( \sqrt { \dfrac {3}{5}}÷ \sqrt {5}= \dfrac { \sqrt {3}}{5}\)
            • 9. 下列计算结果正确的是(  )
              A.(-a)2•a6=-a8
              B.(-a)2•a6=-a8
              C.(-2b23=-6b6
              D.3+=3
            • 10. 下列计算结果正确的是(  )
              A.3+=3
              B.3+=3
              C.(-2b23=-6b6
              D.(-a)2•a6=-a8
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