diff --git a/documents/math-minimal-distance-to-cubic-function/math-minimal-distance-to-cubic-function.pdf b/documents/math-minimal-distance-to-cubic-function/math-minimal-distance-to-cubic-function.pdf index 0c8d8f7..d83ecc9 100644 Binary files a/documents/math-minimal-distance-to-cubic-function/math-minimal-distance-to-cubic-function.pdf and b/documents/math-minimal-distance-to-cubic-function/math-minimal-distance-to-cubic-function.pdf differ diff --git a/documents/math-minimal-distance-to-cubic-function/quadratic-functions.tex b/documents/math-minimal-distance-to-cubic-function/quadratic-functions.tex index 6d11b76..73e2358 100644 --- a/documents/math-minimal-distance-to-cubic-function/quadratic-functions.tex +++ b/documents/math-minimal-distance-to-cubic-function/quadratic-functions.tex @@ -205,12 +205,40 @@ $t$: &= 0 \end{align} -\textbf{Case 2.2:} TODO +\textbf{Case 2.2:} +\todo[inline]{calculate...} \[x = \frac{(1+i \sqrt{3})a}{\sqrt[3]{12} \cdot t} -\frac{(1-i\sqrt{3}) t}{2\sqrt[3]{18}}\] -\textbf{Case 2.3:} TODO +\begin{align} + x^3 &= \underbrace{\left (\frac{(1+i\sqrt{3})a}{\sqrt[3]{12} \cdot t} \right)^3}_{=: \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {1}}}} + \underbrace{- 3 \left(\frac{(1+i\sqrt{3})a}{\sqrt[3]{12} \cdot t} \right)^2 \left(\frac{(1-i\sqrt{3})t}{2 \sqrt[3]{18}} \right)}_{=: \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {2}}}}\\ + &\hphantom{{}=}+ \underbrace{3 \left(\frac{(1+i\sqrt{3})a}{\sqrt[3]{12} \cdot t} \right) \left(\frac{(1-i\sqrt{3})t}{2 \sqrt[3]{18}}\right)^2}_{=: \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {3}}}} + \underbrace{- \left(\frac{(1-i\sqrt{3})t}{2 \sqrt[3]{18}}\right)^3}_{=: \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {4}}}} +\end{align} + +Now simplify the summands: +\begin{align} + \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {1}}} &= + \frac{a^3(1+3i\sqrt{3} - 3 \cdot 3 - \sqrt{27} i)}{12 t^3}\\ + &= \frac{a^3((3\sqrt{3}- \sqrt{27})i - 8)}{12 t^3}\\ + &= \frac{-8a^3}{12 t^3}\\ + &= \frac{-2a^3}{3 t^3}\\ + \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {2}}} &=- 3 \left(\frac{(1+i\sqrt{3})a}{\sqrt[3]{12} \cdot t} \right)^2 \left(\frac{(1-i\sqrt{3})t}{2 \sqrt[3]{18}} \right)\\ + &= \frac{3a(1+2\sqrt{3}i-3)(1-i\sqrt{3})}{t \cdot 2 \cdot 2 \sqrt[3]{3 \cdot 3 \cdot 2 \cdot 18}}\\ + &= \frac{3a(1+2\sqrt{3}i - 3- i\sqrt{3}+2\cdot 3 + i\sqrt[3]{3})}{4t \cdot 3 \sqrt{6}}\\ + &= \frac{a(1-3+4\sqrt{3}i + 6)}{4t\sqrt[3]{6}}\\ + &= \frac{a(4+4\sqrt{3}i)}{4t \sqrt[3]{6}}\\ + &= \frac{a(1+\sqrt{3}i)}{t \sqrt[3]{6}}\\ + \raisebox{.5pt}{\textcircled{\raisebox{-.9pt} {3}}} &= \frac{3(1+i\sqrt{3})a (1-2i\sqrt{3} - 3)t}{\sqrt[3]{12 \cdot 18^2}}\\ + &= \frac{3at((1-2i\sqrt{3}-3)+(i\sqrt{3} + 2\cdot 3 - 3i\sqrt{3}))}{\sqrt[3]{2^2 \cdot 3 \cdot (2 \cdot 3^2)^2}}\\ + &= +\end{align} + + +\textbf{Case 2.3:} +\todo[inline]{calculate...} \[x = \frac{(1-i \sqrt{3})a}{\sqrt[3]{12} \cdot t} -\frac{(1+i\sqrt{3}) t}{2\sqrt[3]{18}}\]