Find curvature r(t) = ( ½ Cost, 1-sint, -3/2 cost)
"r'(t)=\\langle-\\dfrac{1}{2}\\sin t, -\\cos t, \\dfrac{3}{2}\\sin t\\rangle"
"r''(t)=\\langle-\\dfrac{1}{2}\\cos t, \\sin t, \\dfrac{3}{2}\\cos t\\rangle"
"|r'(t)|=\\sqrt{(-\\dfrac{1}{2}\\sin t)^2+( -\\cos t)^2+(\\dfrac{3}{2}\\sin t)^2}"
"=\\dfrac{\\sqrt{10-6\\cos ^2t}}{2}"
"r'(t)\\times r''(t)=\\begin{vmatrix}\n i & j & k \\\\\n\\\\\n -\\dfrac{1}{2}\\sin t & -\\cos t &\\dfrac{3}{2}\\sin t \\\\ \\\\\n -\\dfrac{1}{2}\\cos t & \\sin t &\\dfrac{3}{2}\\cos t\n\\end{vmatrix}"
"=i\\begin{vmatrix}\n -\\cos t & \\dfrac{3}{2}\\sin t \\\\ \\\\\n \\sin t & \\dfrac{3}{2}\\cos t\n\\end{vmatrix}-j\\begin{vmatrix}\n -\\dfrac{1}{2}\\sin t & \\dfrac{3}{2}\\sin t \\\\ \\\\\n -\\dfrac{1}{2}\\cos t& \\dfrac{3}{2}\\cos t\n\\end{vmatrix}"
"+k\\begin{vmatrix}\n -\\dfrac{1}{2}\\sin t & -\\cos t \\\\ \\\\\n -\\dfrac{1}{2}\\cos t & \\sin t\n\\end{vmatrix}=-\\dfrac{3}{2}i-\\dfrac{1}{2}k"
"|r'(t)\\times r''(t)|=\\sqrt{(-\\dfrac{3}{2})^2+(0)^2+(-\\dfrac{1}{2})^2}=\\dfrac{\\sqrt{10}}{2}"
Find curvature
"=\\dfrac{\\dfrac{\\sqrt{10}}{2}}{(\\dfrac{\\sqrt{10-6\\cos ^2t}}{2})^{3}}"
"=\\dfrac{4\\sqrt{10}}{(10-6\\cos ^2t)^{3\/2}}"
"=\\dfrac{2\\sqrt{5}}{(5-3\\cos ^2t)^{3\/2}}"
"\\kappa(t)=\\dfrac{2\\sqrt{5}}{(5-3\\cos ^2t)^{3\/2}}"
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