优优班--学霸训练营 > 知识点挑题
全部资源
          排序:
          最新 浏览

          50条信息

            • 1.

              在\(\Delta ABC\)中,角\(A,B,C\)的对边分别为\(a,b,c\),若\({{a}^{2}}+{{b}^{2}}=2017{{c}^{2}}\),则\(\dfrac{{\tan }C}{{\tan }A}+\dfrac{{\tan }C}{{\tan }B}=(\)    \()\)

              A.\(\dfrac{{1}}{{2016}}\)
              B.\(\dfrac{{1}}{{2017}}\)
              C.\(\dfrac{{1}}{{1008}}\)
              D.\(\dfrac{{2}}{{2017}}\)
            • 2.

              如下图所示,为了测量某障碍物两侧\(A\),\(B\)向的距离,给定下列四组数据,计算时应当用的数据组为(    )

              A.\(α\),\(a\)
              B.\(β\),\(a\)
              C.\(a\),\(b\),\(γ\)
              D.\(β\),\(b\)
            • 3.

              \(\triangle ABC\)的三边分别为\(a\),\(b\),\(c\),且\(a=1\),\(B=45^{\circ}\),\(S_{\triangle ABC}=2\),则\(\triangle ABC\)的外接圆的直径为\((\)  \()\)

              A.\(4 \sqrt{3}\)
              B.\(5\)

              C.\(5 \sqrt{2}\)
              D.\(6 \sqrt{2}\)
            • 4.

              在\(\Delta ABC\)中,内角\(A,B,C\)所对的边分别是\(a,b,c\),若\(a\sin A=b\sin B+(c-b)\sin C\),则角\(A\)的值为

              A.\(\dfrac{\pi }{6}\)
              B.\(\dfrac{\pi }{4}\)
              C.\(\dfrac{\pi }{3}\)
              D.\(\dfrac{2\pi }{3}\)
            • 5.

              已知在三棱锥\(S-ABC\)中,侧棱\(SA⊥\)底面\(ABC\),\(AB=5\),\(BC=8\),\(∠B=60^{\circ}\),\(SA={2}\sqrt{{5}}\),则该三棱锥的外接球的表面积为

              A.\(\dfrac{{64}}{{3}}{ }\!\!\pi\!\!{ }\)
              B.\(\dfrac{{256}}{{3}}{ }\!\!\pi\!\!{ }\)
              C.\(\dfrac{{436}}{{3}}{ }\!\!\pi\!\!{ }\)
              D.\(\dfrac{{2048}\sqrt{{3}}}{{27}}{ }\!\!\pi\!\!{ }\)
            • 6.

              在\(\triangle ABC\)中,若\(a=7,b=8,\cos C=\dfrac{13}{14}\),则最大角的余弦是       \((\)  \()\)

              A. \(-\dfrac{1}{5}\)
              B.\(-\dfrac{1}{6}\)
              C.\(-\dfrac{1}{7}\)
              D.\(-\dfrac{1}{8}\) 
            • 7.
              在\(\triangle ABC\)中,若\(BC= \sqrt {3}\),\(AC= \sqrt {2}\),\(∠B=45^{\circ}\),则\(∠A=(\)  \()\)
              A.\(60^{\circ}\)或\(120^{\circ}\)
              B.\(60^{\circ}\)
              C.\(30^{\circ}\)或\(150^{\circ}\)
              D.\(30^{\circ}\)
            • 8.

              在\(\Delta ABC\)中,若\({{\sin }^{2}}(B+C)+{{\cos }^{2}}B+{{\cos }^{2}}C+\sin B\sin C\geqslant 2\),则角\(A\)的取值范围是(    )

              A.\((0,\dfrac{\pi }{6}]\)
              B.\([\dfrac{\pi }{3},\dfrac{\pi }{2}]\)
              C.\((0,\dfrac{\pi }{3}]\)
              D.\([\dfrac{\pi }{3},\pi ) \)
            • 9.
              在\(\triangle \) \(ABC\)中, \(a\)\(b\)\(c\)分别是内角 \(A\)\(B\)\(C\)的对边\(.\)若 \(b\)\(\sin \) \(A\)\(=3\) \(c\)\(\sin \) \(B\)\(a\)\(=3\),\(\cos \) \(B\)\(= \dfrac{2}{3}\),则 \(b\)\(=\)(    )
              A.\(14\)                                     
              B.\(6\)
              C.\( \sqrt{14}\)                           
              D.\( \sqrt{6}\)
            • 10.

              在\(\triangle ABC\) 中,角\(A\),\(B\),\(C\)所对的边分别为\(a\),\(b\),\(c\),则“\( \dfrac{c-b}{c-a}= \dfrac{\sin A}{\sin C+\sin B} \) ”是“角\(A\),\(B\),\(C\)成等差数列”的

              A.充分不必要条件                                        
              B.必要不充分条件

              C.充要条件                                                   
              D.既不充分也不必要条件
            0/40

            进入组卷