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X₈₅₁¶

X₆₅-HIRST INVERSE OF X₇₃

X₈₅₁ (X₆₅-HIRST INVERSE OF X₇₃) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_851 = X_65-HIRST INVERSE OF X_73."""

        from __future__ import annotations

        from pathlib import Path

        import sympy.geometry as spg
        from geometor.model import Model

        from geometor.etc.ops import (
            central_line,
            centroid_of,
            circumcenter_of,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_00851(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_851 = X_65-HIRST INVERSE OF X_73 on reference triangle ABC."""
            X_851 = eval_trilinear_point(model, A, B, C, 'sin(2*B)*sin(C - A) + sin(2*C)*sin(B - A)', ID="X_851", classes=["selected", "target"])
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center"])
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center"])
            central_line(model, X_2, X_3, 2, 3)
            X_43 = eval_trilinear_point(model, A, B, C, 'a*b + a*c - b*c', ID="X_43", classes=["center", "incident"])
            X_46 = eval_trilinear_point(model, A, B, C, 'cos(B) + cos(C) - cos(A)', ID="X_46", classes=["center", "incident"])
            central_line(model, X_43, X_46, 43, 46, incident=True)
            X_42 = eval_trilinear_point(model, A, B, C, 'a*(b + c)', ID="X_42", classes=["center", "incident"])
            X_65 = eval_trilinear_point(model, A, B, C, 'cos(B) + cos(C)', ID="X_65", classes=["center", "incident"])
            central_line(model, X_42, X_65, 42, 65, incident=True)
            return promote_point_to_top(model, X_851)


        def build_model(
            sides: tuple[float, float, float] = (5.0, 6.0, 7.0),
            show_guides: bool = False,
        ) -> Model:
            """Build a `geometor.model.Model` for X_851 on the given reference triangle."""
            model = create_model('X_851 = X_65-HIRST INVERSE OF X_73')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_00851(model, A, B, C)
            return model


        if __name__ == "__main__":
            here = Path(__file__).resolve().parent
            model_acute = build_model((5.0, 6.0, 7.0))
            model_acute.save(str(here / "x-00851.json"))
            write_center_svg(
                model_acute,
                here / "x-00851.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X851¶

X₈₅₁¶