It appears you cannot make a LaTeX equation in the Wiki, but it may be possible, for instance to place a link to a mathematical formula.

[http://latex.codecogs.com/gif.latex?%5Cbegin%7Bpmatrix%7D%20ct%27%5C%5C%20x%27%20%5Cend%7Bpmatrix%7D%20%3D%20%5Cbegin%7Bpmatrix%7D%20-%5Cbeta%20%5Cgamma%20%26%20%5Cgamma%20%5C%5C%20%5Cgamma%20%26%20-%5Cbeta%20%5Cgamma%20%5Cend%7Bpmatrix%7D%20%5Cbegin%7Bpmatrix%7D%20ct%5C%5C%20x%20%5Cend%7Bpmatrix%7D]

This is available from http://www.codecogs.com/latex/eqneditor.php under the "URL encoded" format.

Also, you may be able to see a list of characters here to copy and paste at the top of mathematical documents, so that you can use them.

α β � Γ ∂ δ ε ϵ ζ η θ Θ ι κ λ Λ μ ν ξ ο ° π ρ ς σ τ υ ∩ φ Φ χ ψ ω Ω ~ ≈ ≠ ≡ ± ≤ ≥ Δ ∇ Σ ∂ ∫ ∏ → ↔ ∞ • ∙ ♠ ♣ ♥ ♦ -JonDoolin

(This does NOT work on all phpwiki's; it may be site dependent.)

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You can hack WardsWiki to render this as an inline image as follows (look at the source Luke):

http://latex.codecogs.com/gif.latex?%5Cbegin%7Bpmatrix%7D%20ct%27%5C%5C%20x%27%20%5Cend%7Bpmatrix%7D%20%3D%20%5Cbegin%7Bpmatrix%7D%20-%5Cbeta%20%5Cgamma%20%26%20%5Cgamma%20%5C%5C%20%5Cgamma%20%26%20-%5Cbeta%20%5Cgamma%20%5Cend%7Bpmatrix%7D%20%5Cbegin%7Bpmatrix%7D%20ct%5C%5C%20x%20%5Cend%7Bpmatrix%7D&a.gif

Note the "&a.gif" at the end. It clutters the image a bit, but tricks the wiki-engine into believing this to be an image (probably just pattern matching at the end).