优优班--学霸训练营 > 知识点挑题
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            • 1.
              如图所示,观察四个几何体,其中判断正确的是\((\)  \()\)
              A.
              是棱台
              B.
              是圆台
              C.
              是棱锥
              D.
              不是棱柱
            • 2.
              已知直三棱柱\(ABC-A_{1}B_{1}C_{1}\)的侧棱长为\(6\),且底面是边长为\(2\)的正三角形,用一平面截此棱柱,与侧棱\(AA_{1}\),\(BB_{1}\),\(CC_{1}\),分别交于三点\(M\),\(N\),\(Q\),若\(\triangle MNQ\)为直角三角形,则该直角三角形斜边长的最小值为\((\)  \()\)
              A.\(2 \sqrt {2}\)
              B.\(3\)
              C.\(2 \sqrt {3}\)
              D.\(4\)
            • 3.
              如图,正方体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)绕其体对角线\(BD_{1}\)旋转\(θ\)之后与其自身重合,则\(θ\)的值可以是\((\)  \()\)
              A.\( \dfrac {5π}{6}\)
              B.\( \dfrac {3π}{4}\)
              C.\( \dfrac {2π}{3}\)
              D.\( \dfrac {3π}{5}\)
            • 4.
              如图为一正方体的平面展开图,在这个正方体中,有下列四个命题:
              \(①AF⊥GC\);
              \(②BD\)与\(GC\)成异面直线且夹角为\(60^{\circ}\);
              \(③BD/\!/MN\);
              \(④BG\)与平面\(ABCD\)所成的角为\(45^{\circ}\).
              其中正确的个数是\((\)  \()\)
              A.\(1\)
              B.\(2\)
              C.\(3\)
              D.\(4\)
            • 5.
              在正方体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,给出下列四个推断:
              \(①A_{1}C_{1}⊥AD_{1}\)
              \(②A_{1}C_{1}⊥BD\)
              \(③\)平面\(A_{1}C_{1}B/\!/\)平面\(ACD_{1}\)
              \(④\)平面\(A_{1}C_{1}B⊥\)平面\(BB_{1}D_{1}D\)
              其中正确的推断有\((\)  \()\)
              A.\(1\)个
              B.\(2\)个
              C.\(3\)个
              D.\(4\)个
            • 6.
              设正三棱锥\(P-ABC\)的高为\(H\),且此棱锥的内切球的半径\(R= \dfrac {1}{7}H\),则\( \dfrac {H^{2}}{PA^{2}}=(\)  \()\)
              A.\( \dfrac {29}{39}\)
              B.\( \dfrac {32}{39}\)
              C.\( \dfrac {34}{39}\)
              D.\( \dfrac {35}{39}\)
            • 7.
              如图,\(ABCD-A_{1}B_{1}C_{1}D_{1}\)为正方体,下面结论错误的是\((\)  \()\)
              A.\(BD/\!/\)平面\(CB_{1}D_{1}\)
              B.\(AC_{1}⊥BD\)
              C.\(AC_{1}⊥\)平面\(CB_{1}D_{1}\)
              D.异面直线\(AD\)与\(CB_{1}\)所成的角为\(60^{\circ}\)
            • 8.
              如图,在三棱锥\(A-BCD\)中,\(AC⊥AB\),\(BC⊥BD\),平面\(ABC⊥\)平面\(BCD\).
              \(①AC⊥CD②AD⊥BC③\)平面\(ABC⊥\)平面\(ABD④\)平面\(ACD⊥\)平面\(ABD\).
              以上结论正确的个数有\((\)  \()\)
              A.\(1\)
              B.\(2\)
              C.\(4\)
              D.\(5\)
            • 9.
              已知三棱柱\(ABC-A_{1}B_{1}C_{1}\)的六个顶点都在球\(O\)的球面上,球\(O\)的表面积为\(194π\),\(AA_{1}⊥\)平面\(ABC\),\(AB=5\),\(BC=12\),\(AC=13\),则直线\(BC_{1}\)与平面\(AB_{1}C_{1}\)所成角的正弦值为\((\)  \()\)
              A.\( \dfrac {5 \sqrt {3}}{52}\)
              B.\( \dfrac {7 \sqrt {3}}{52}\)
              C.\( \dfrac {5 \sqrt {2}}{26}\)
              D.\( \dfrac {7 \sqrt {2}}{26}\)
            • 10.
              已知四棱锥\(S-ABCD\)的底面是正方形,侧棱长均相等,\(E\)是线段\(AB\)上的点\((\)不含端点\().\)设\(SE\)与\(BC\)所成的角为\(θ_{1}\),\(SE\)与平面\(ABCD\)所成的角为\(θ_{2}\),二面角\(S-AB-C\)的平面角为\(θ_{3}\),则\((\)  \()\)
              A.\(θ_{1}\leqslant θ_{2}\leqslant θ_{3}\)
              B.\(θ_{3}\leqslant θ_{2}\leqslant θ_{1}\)
              C.\(θ_{1}\leqslant θ_{3}\leqslant θ_{2}\)
              D.\(θ_{2}\leqslant θ_{3}\leqslant θ_{1}\)
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