\(A=1-\dfrac{\tan20^0}{\tan20^0}=1-1=0\\ B=\left(\cos^225^0+\cos^265^0\right)+\left(\cos^235^0+\cos^255^0\right)+\cos^245^0\\ B=\left(\cos^225^0+\sin^225^0\right)+\left(\cos^235^0+\sin^235^0\right)+\left(\dfrac{\sqrt{2}}{2}\right)^2\\ B=1+1+\dfrac{1}{2}=\dfrac{5}{2}\\ C=\dfrac{2\cdot\dfrac{1}{2}-\dfrac{\sqrt{3}}{2}}{\left(\dfrac{\sqrt{3}}{2}\right)^2-\dfrac{1}{2}}=\left(1-\dfrac{\sqrt{3}}{2}\right):\left(\dfrac{3}{4}-\dfrac{1}{2}\right)=\dfrac{2-\sqrt{3}}{2}\cdot4=2\left(2-\sqrt{3}\right)=4-2\sqrt{3}\)
\(D=\sin^225^0+\cos^225^0-\tan35^0+\tan35^0-\dfrac{\tan58^0}{\tan58^0}\\ D=1+0-1=0\)
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