A few questions showing how to use custom constants in different contexts.
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", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "\\begin{align}
\\mathrm{j} &= \\sqrt{-1} \\\\[1em]
z_1 &= \\var{z1} \\\\[1em]
z_2 &= \\var{z2}
\\end{align}
What is $z_1 \\times z_2$?
\nTry {z1*z2} and {re(z1*z2)} {if(im(z1*z2)<0,'-','+')} {abs(im(z1*z2))}*i.
The letters i, j and k are used to represent the standard 3D unit vectors.
", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "$\\mathbf{v_1} = \\simplify{i + z*k}$.
\n$\\mathbf{v_2} = \\simplify{{a}i + {b}j + {c}k}$.
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\nWrite your answer in terms of the unit vectors $\\var{i}$, $\\var{j}$ and $\\var{k}$.
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", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "$\\tau = 2\\pi$.
\nHere's a random multiple of $\\tau$: $\\var{multiple_of_tau}$.
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\nTry tau/{p} or 2pi/{p}