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            • 1.
              已知函数\(f(x)=2\sin x\cos x-\sin ^{2}x+1\),当\(x=θ\)时函数\(y=f(x)\)取得最小值,则\( \dfrac {\sin 2θ+\cos 2θ}{\sin 2\theta -\cos 2\theta }=(\)  \()\)
              A.\(-3\)
              B.\(3\)
              C.\(- \dfrac {1}{3}\)
              D.\( \dfrac {1}{3}\)
            • 2.
              \(\cos 36^{\circ}\cos 96^{\circ}+\sin 36^{\circ}\sin 84^{\circ}\)的值是 ______
            • 3.

              已知\(\cos (α- \dfrac {π}{6})+\sin α= \dfrac {4}{5} \sqrt {3}\),则\(\sin (α+ \dfrac {7π}{6})\)的值是\((\)  \()\)
              A.\(- \dfrac {2 \sqrt {3}}{5}\)
              B.\( \dfrac {2 \sqrt {3}}{5}\)
              C.\(- \dfrac {4}{5}\)
              D.\( \dfrac {4}{5}\)
            • 4.
              \(\sin 10^{\circ}\sin 30^{\circ}\sin 50^{\circ}\sin 70^{\circ}=\) ______ .
            • 5.
              若点\(P(\sin 2018^{\circ},\cos 2018^{\circ})\),则\(P\)在\((\)  \()\)
              A.第一象限
              B.第二象限
              C.第三象限
              D.第四象限
            • 6.

              在\(\vartriangle ABC\)中,点\(D\)在边\(AB\)上,\(CD\bot BC,\ AC=5\sqrt{3},\ \) \(CD=5,\ \) \(BD=2AD\),则\(AD\)的长为    

            • 7.

              已知,则\(\cos (2α+ \dfrac{3π}{5}) \)

              A.\(- \dfrac{7}{9} \)
              B.\(- \dfrac{1}{9} \)
              C.\( \dfrac{1}{9} \)
              D.\( \dfrac{7}{9} \)
            • 8.

              已知曲线\(C\)的极坐标方程为\({ρ}^{2}= \dfrac{1}{3co{s}^{2}θ+si{n}^{2}θ} \),以极点为平面直角坐标系的原点,极轴为\(x\)轴的正半轴建立平面直角坐标系.

              \((1)\)求曲线\(C\)的普通方程;

              \((2)\)\(A\)\(B\)为曲线\(C\)上两个点,若\(OA\)\(⊥\)\(OB\),求\( \dfrac{1}{|OA{|}^{2}}+ \dfrac{1}{|OB{|}^{2}} \)的值。

            • 9.

              计算\(\dfrac{\cos {{10}^{0}}-\sqrt{3}\cos (-{{100}^{0}})}{\sqrt{1-\sin {{10}^{0}}}}=\)          \(.(\)用数字做答\()\)

            • 10. 已知0<β<<α<,cos(-α)=,sin(+β)=,求sin(α+β)的值.
            0/40

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