## X(450) (X(3)-HIRST INVERSE OF X(4))

 Interactive Applet

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This applet was built with the free and multiplatform dynamic geometry software C.a.R..

 Information from Kimberling's Encyclopedia of Triangle Centers

Trilinears           f(A,B,C) : f(B,C,A) : f(C,A,B), where f(A,B,C) = (sec A)[cos4A - (cos B cos C)2]
= g(A,B,C) : g(B,C,A) : g(C,A,B), where g(A,B,C) = (cos A)[sec4A - (sec B sec C)2]

Barycentrics    h(A,B,C) : h(B,C,A) : h(C,A,B), where h(A,B,C) = (tan A)(cos4A - (cos B cos C)2]

X(450) lies on these lines: 2,3    107,511    155,1075    1092,1093

X(450) = isogonal conjugate of X(1942)
X(450) = crossdifference of any two points on line X(185)X(647)
X(450) = X(3)-Hirst inverse of X(4)

This is a joint work of
Humberto José Bortolossi, Lis Ingrid Roque Lopes Custódio and Suely Machado Meireles Dias.