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            • 1.
              在\(\triangle ABC\)中,\(\tan A= \dfrac { \sqrt {2}}{3}\),则\(\sin A=\) ______ .
            • 2.
              已知\(α∈(0, \dfrac {π}{2})\),\(β∈( \dfrac {π}{2},π)\)且\(\sin (α+β)= \dfrac {3}{5}\),\(\cos β=- \dfrac {5}{13}\),求\(\sin α\)的值.
            • 3.
              函数\(y=\cos x⋅|\tan x|(- \dfrac {π}{2} < x < \dfrac {π}{2})\)的大致图象是\((\)  \()\)
              A.
              B.
              C.
              D.
            • 4.
              已知\(\tan θ=2\),则\(\sin ^{2}θ+\sin θ\cos θ-2\cos ^{2}θ=(\)  \()\)
              A.\(- \dfrac {4}{3}\)
              B.\( \dfrac {5}{4}\)
              C.\(- \dfrac {3}{4}\)
              D.\( \dfrac {4}{5}\)
            • 5.
              已知\(2\sin 2α=1+\cos 2α\),则\(\tan 2α=(\)  \()\)
              A.\( \dfrac {4}{3}\)或\(0\)
              B.\(- \dfrac {4}{3}\)或\(0\)
              C.\( \dfrac {4}{3}\)
              D.\(- \dfrac {4}{3}\)
            • 6.
              已知\(α\)是第四象限角,\(\tan α=- \dfrac {5}{12}\),则\(\sin α=(\)  \()\)
              A.\( \dfrac {1}{5}\)
              B.\( \dfrac {5}{13}\)
              C.\(- \dfrac {5}{13}\)
              D.\(- \dfrac {1}{5}\)
            • 7.
              已知\(\sin ( \dfrac {π}{3}+α)= \dfrac {1}{3}\),则\(\cos ( \dfrac {5π}{6}+α)=(\)  \()\)
              A.\( \dfrac {1}{3}\)
              B.\(- \dfrac {1}{3}\)
              C.\( \dfrac {2 \sqrt {2}}{3}\)
              D.\(- \dfrac {2 \sqrt {2}}{3}\)
            • 8.
              已知\(\tan α=2\),则\(4\sin ^{2}α-3\sin α\cos α-5\cos ^{2}α=\) ______ .
            • 9.
              已知\(f(α)= \dfrac {\sin (π+α)\cos (2π-α)\tan (-α)}{\tan (-\pi -\alpha )\cos ( \dfrac {3π}{2}+\alpha )}\).
              \((1)\)化简\(f(α)\);
              \((2)\)当\(α=- \dfrac {31π}{3}\)时,求\(f(α)\)的值;
              \((3)\)若\(α\)是第三象限的角,且\(\sin α=- \dfrac {1}{5}\),求\(f(α)\)的值.
            • 10.
              已知\(\tan α=2\),求下列各式的值
              \((1) \dfrac {\sin α+2\cos α}{4\cos \alpha -\sin \alpha }\)
              \((2)\sin α\cos α+\cos ^{2}α\)
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