ข้อ 2)
$T=(sin\theta+sin^3\theta+...)+(cos^2\theta+cos^4\theta+...)$
$T=\frac{sin\theta}{1-sin^2\theta}+\frac{cos^2\theta}{1-cos^2\theta}$
$T=\frac{sin^3\theta+cos^4\theta}{sin^2\theta cos^2\theta}$
$3T(\frac{\pi}{3})=3\bigg[\frac{sin^3(\frac{\pi}{3})+cos^4(\frac{\pi}{3})}{sin^2(\frac{\pi}{3})cos^2(\frac{\pi}{3})}\bigg]$
$3T(\frac{\pi}{3})=3\bigg[\frac{{(\frac{\sqrt{3}}{2})}^3+{(\frac{1}{2})}^4}{(\frac{3}{4})(\frac{1}{4})}\bigg]$
$3T(\frac{\pi}{3})=6\sqrt{3}+1$
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