优优班--学霸训练营 > 知识点挑题
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            • 1. 如图,四棱锥\(P-ABCD\)中,底面\(ABCD\)是直角梯形,\(AB/\!/CD\),\(∠DAB=60^{\circ}\),\(AB=AD=2CD\),侧面\(PAD⊥\)底面\(ABCD\),且\(\triangle PAD\)为等腰直角三角形,\(∠APD=90^{\circ}\),\(M\)为\(AP\)的中点.
              \((1)\)求证:\(AD⊥PB\);
              \((2)\)求证:\(DM/\!/\)平面\(PCB\).
            • 2.

              四边形\(ABCD\)的内角\(A\)与\(C\)互补,\(AB=1\),\(BC=3\),\(CD=DA=2\).

              \((1)\)求\(C\)和\(BD;\)

              \((2)\)求四边形\(ABCD\)的面积.

            • 3. 如图所示,在四边形\(ABCD\)中,\(∠D=2∠B\),且\(AD=1\),\(CD=3\),\(\cos ∠B= \dfrac { \sqrt {3}}{3}\)
              \((1)\)求\(\triangle ACD\)的面积;
              \((2)\)若\(BC=2 \sqrt {3}\),求\(AB\)的长.
            • 4. 在\(\triangle ABC\)中,已知\(a=10\),\(∠B=45^{\circ}\),\(∠A=30^{\circ}\),解此三角形.
            • 5. 如图,正方形\(ABCD\)中,以\(D\)为圆心、\(DA\)为半径的圆弧与以\(BC\)为直径的半圆\(O\)交于点\(F\),连接\(CF\)并延长交\(AB\)于点\(E\).
              \((\)Ⅰ\()\)求证:\(AE=EB\);
              \((\)Ⅱ\()\)若\(EF⋅FC= \dfrac {4}{5}\),求正方形\(ABCD\)的面积.
            • 6.
              如图所示,在四边形\(ABCD\)中,\(∠D=2∠B\),且\(AD=1\),\(CD=3\),\(\cos ∠B= \dfrac { \sqrt {3}}{3}\)
              \((1)\)求\(\triangle ACD\)的面积;
              \((2)\)若\(BC=2 \sqrt {3}\),求\(AB\)的长.
            • 7.
              如图,在\(\triangle ABC\)中,\(∠ABC=90^{\circ}\),\(BD⊥AC\),\(D\)为垂足,\(E\)为\(BC\)的中点,求证:\(∠EDC=∠ABD\).
            • 8.
              如图,正方形\(ABCD\)中,以\(D\)为圆心、\(DA\)为半径的圆弧与以\(BC\)为直径的半圆\(O\)交于点\(F\),连接\(CF\)并延长交\(AB\)于点\(E\).
              \((\)Ⅰ\()\)求证:\(AE=EB\);
              \((\)Ⅱ\()\)若\(EF⋅FC= \dfrac {4}{5}\),求正方形\(ABCD\)的面积.
            • 9.
              选修\(4—1\):几何证明选讲

              如图,\(AC\)是圆\(O\)的切线,\(A\)是切点,\(AD⊥OE\)于\(D\),割线\(EC\)交圆\(O\)于\(B\)、\(C\)两点.

              \((1)\)证明:\(O\)、\(D\)、\(B\)、\(C\)四点共圆;

              \((2)\)设\(∠DBC=50^{\circ}\),\(∠ODC=30^{\circ}\),求\(∠OEC\)的大小.

            • 10.
              选做题:平面几何
              已知在\(\triangle ABC\)中,\(AB=AC\),以\(AB\)为直径的\(⊙O\)交\(BC\)于\(D\),过\(D\)点作\(⊙O\)的切线交\(AC\)于\(E\).
              求证:\((1)DE⊥AC\);\(\)
              \((2)BD^{2}=CE⋅CA\).
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