Mathematica Cheat Sheet

• 怎样用Mathematica解带字母的方程组？
• Clear Variable. Clear["Global`*"];
• Variable is positive real with assumptions. ref

$Assumptions = Element[Subscript[\[Theta], 1], Reals] && Element[Subscript[\[Theta], 2], Reals]

• \((-1)^{\frac{1}{3}}=e^{\pi i/3}=\cos(\pi/3)+i\sin(\pi/3)\)