Editing Morley's trisector theorem (section)

==Related triangle centers==

The '''Morley center''', ''X''(356), [[centroid]] of the first Morley triangle, is given in [[trilinear coordinates]] by

<math display=block>
\cos\tfrac13A + 2\cos\tfrac13B\,\cos\tfrac13C \,:\, \cos\tfrac13B + 2\cos\tfrac13C\,\cos\tfrac13A \,:\, \cos\tfrac13C + 2\cos\tfrac13A\,\cos\tfrac13B
</math>

'''1st Morley–Taylor–Marr center''', ''X''(357): The first Morley triangle is [[perspective (geometry)|perspective]] to triangle {{nobr|<math>\triangle ABC</math>{{sfn|Taylor Marr|1913}} :<ref>Fox, M. D.; and Goggins, J. R. "Morley's diagram generalised", ''[[Mathematical Gazette]]'' 87, November 2003, 453–467.</ref>}}<< the lines each connecting a vertex of the original triangle with the opposite vertex of the Morley triangle [[concurrent lines|concur]] at the point

<math display=block>
\sec\tfrac13A \,:\, \sec\tfrac13B \,:\, \sec\tfrac13C
</math>