优优班--学霸训练营 > 知识点挑题
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            • 1.

              如图,点列\(\{An\}\),\(\{Bn\}\)分别在某锐角的两边上,且\(\left| {{A}_{n}}{{A}_{n+1}} \right|=\left| {{A}_{n+1}}{{A}_{n+2}} \right|,{{A}_{n}}\ne {{A}_{n+2}},n\in {{N}^{*}}\) ,\(\left| {{B}_{n}}{{B}_{n+1}} \right|=\left| {{B}_{n+1}}{{B}_{n+2}} \right|,{{B}_{n}}\ne {{B}_{n+2}},n\in {{N}^{*}} .(P\neq Q\)表示点\(P\)与\(Q\)不重合\()\)若\({d}_{n}=\left|{A}_{n}{B}_{n}\right|,{S}_{n} \)为\(∆{A}_{n}{B}_{n}{B}_{n+1} \)的面积,则

              A.\(\;\{\;S_{n}\;\}\; \) 是等差数列  
              B.\(\;\{\;S_{n}^{2}\;\}\; \) 是等差数列  
              C.\(\;\{\;d_{n}\;\}\; \) 是等差数列  
              D.\(\;\{\;d_{n}^{2}\;\}\; \) 是等差数列
            • 2.
              在\(\triangle ABC\)中,\(∠ABC=90^{\circ}\),\(AB= \sqrt {3}\),\(BC=2\),点\(P\)为\(\triangle ABC\)内一点,若\(∠BPC=90^{\circ}\),\(PB=1\),则\(PA=(\)  \()\)
              A.\(4- \sqrt {3}\)
              B.\( \dfrac { \sqrt {7}}{2}\)
              C.\( \sqrt {7}\)
              D.\(1\)
            • 3.
              如图,在矩形\(ABCD\)中,\(AD=6\),\(AE⊥BD\),垂足为\(E\),\(ED=3BE\),点\(P\),\(Q\)分别在\(BD\),\(AD\)上,
              则\(AP+PQ\)的最小值为\((\)  \()\)
              A.\(2 \sqrt {2}\)
              B.\( \sqrt {2}\)
              C.\(2 \sqrt {3}\)
              D.\(3 \sqrt {3}\)
            • 4.
              若三角形的三条边之比为\(3\):\(5\):\(7\),与它相似的三角形的最长边为\(21cm\),则其余两边的长度之和为\((\)  \()\)
              A.\(24cm\)
              B.\(21cm\)
              C.\(19cm\)
              D.\(9cm\)
            • 5.
              如图所示,\(P\)、\(Q\)分别在\(BC\)和\(AC\)上,\(BP\):\(CP=2\):\(5\),\(CQ\):\(QA=3\):\(4\),则\( \dfrac {AR}{RP}(\)  \()\)
              A.\(3\):\(14\)
              B.\(14\):\(3\)
              C.\(17\):\(3\)
              D.\(17\):\(14\)
            • 6.
              如图,在正三角形\(ABC\)中,\(D\)、\(E\)分别在\(AC\)、\(AB\)上,\( \dfrac {AD}{AC}= \dfrac {1}{3}\),\(AE=BE\),则有\((\)  \()\)
              A.\(\triangle AED\)∽\(\triangle BED\)
              B.\(\triangle AED\)∽\(\triangle CBD\)
              C.\(\triangle AED\)∽\(\triangle ABD\)
              D.\(\triangle BAD\)∽\(\triangle BCD\)
            • 7.
              如图所示,梯形\(ABCD\)的对角线交于点\(O\),则下列四个结论:
              \(①\triangle AOB\)∽\(\triangle COD\);
              \(②\triangle AOD\)∽\(\triangle ACB\);
              \(③S_{\triangle DOC}\):\(S_{\triangle AOD}=CD\):\(AB\);
              \(④S_{\triangle AOD}=S_{\triangle BOC}\).
              其中正确的个数为\((\)  \()\)
              A.\(1\)
              B.\(2\)
              C.\(3\)
              D.\(4\)
            • 8.
              如图所示,在▱\(ABCD\)中,\(E\)为\(CD\)上一点,\(DE\):\(CE=2\):\(3\),连接\(AE\),\(BE\),\(BD\),且\(AE\),\(BD\)交与点\(F\),则\(S_{\triangle DEF}\):\(S_{\triangle EBF}\):\(S_{\triangle ABF}\)等于\((\)  \()\)
              A.\(4\):\(10\):\(25\)
              B.\(4\):\(9\):\(25\)
              C.\(2\):\(3\):\(5\)
              D.\(2\):\(5\):\(25\)
            • 9.
              如图所示,在\(\triangle ABC\)中,\(AD⊥BC\)于\(D\),下列条件:
              \((1)∠B+∠DAC=90^{\circ}\);
              \((2)∠B=∠DAC\);
              \((3) \dfrac {CD}{AD}= \dfrac {AC}{AB}\);
              \((4)AB^{2}=BD⋅BC\).
              其中一定能够判定\(\triangle ABC\)是直角三角形的共有\((\)  \()\)
              A.\(3\)个
              B.\(2\)个
              C.\(1\)个
              D.\(0\)个
            • 10.
              如图所示,在直角梯形\(ABCD\)中,\(AB=7\),\(AD=2\),\(BC=3.\)如果\(AB\)边上的点\(P\)使得以\(P\),\(A\),\(D\)为顶点的三角形和以\(P\),\(B\),\(C\)为顶点的三角形相似,那么这样的点\(P\)有\((\)  \()\)
              A.\(1\)个
              B.\(2\)个
              C.\(3\)个
              D.\(2\)个
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