Prove that
gamma=(a(3u,u^ 8 ), 3a * u ^ 2, 3a * (3u + u ^ 3)
tau = 1/(k ^ 2) * (r*gamma)
"\\gamma=(a(3u+u^ 8 ), 3a u ^ 2, 3a (3u + u ^ 3))"
"\\tau=\\frac{r\\gamma}{k^2}"
torsion:
"\\tau=\\frac{(\\gamma'\\times \\gamma'')\\cdot\\gamma'''}{|\\gamma'\\times \\gamma''|^2}"
curvature:
"k=\\frac{|\\gamma'\\times \\gamma''|}{|\\gamma'|^3}"
then:
"(\\gamma'\\times \\gamma'')\\cdot\\gamma'''=|\\gamma'|^6r\\gamma"
"\\gamma'=(a(3+8u^ 7 ), 6au , 3a (3 + 3u ^2))"
"\\gamma''=(56au^ 6 , 6a , 18au)"
"\\gamma'''=(336au^ 5 , 0 , 18a)"
"(\\gamma'\\times \\gamma'')\\cdot\\gamma'''=\\begin{vmatrix}\n a(3+8u^ 7 ) & 6au& 3a (3 + 3u ^2)\\\\\n 56au^ 6 & 6a&18au\\\\\n336au^ 5&0&18a\n\\end{vmatrix}="
"=-6au(1008a^2u^6-6048a^2u^6)+6a(54a^2+144a^2u^7-3024a^2u^5-3024a^2u^7)="
"=12960a^3u^7-18144a^3u^5+324a^3"
"|\\gamma'|^6=((3a+8au^ 7 )^2+36a^2u ^ 2+(9a + 9au ^ 2))^3"
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