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X₃₃₉₈¶

COS(A - 2ω) POINT

X₃₃₉₈ and related points occupy Bernard Gibert’s Table 38. See the note at X₃₃₆₄.

X₃₃₉₈ (COS(A - 2ω) POINT) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_3398 = COS(A - 2ω) POINT."""

        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,
            circumcenter_of,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            midpoint,
            nine_point_center_of,
            promote_point_to_top,
            symmedian_point_of,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_03398(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_3398 = COS(A - 2ω) POINT on reference triangle ABC."""
            X_1342 = eval_trilinear_point(model, A, B, C, 'sin(A) + cos(A)*cot( omega  /2)', ID="X_1342", classes=["center"])
            X_1343 = eval_trilinear_point(model, A, B, C, 'sin(A) - cos(A)*tan( omega  /2)', ID="X_1343", classes=["center"])
            X_3398 = midpoint(model, X_1342, X_1343, ID="X_3398", classes=["selected", "target"], guide=False)
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center", "incident"])
            X_6 = symmedian_point_of(model, A, B, C, ID="X_6", classes=["center", "incident"])
            central_line(model, X_3, X_6, 3, 6, incident=True)
            X_5 = nine_point_center_of(model, A, B, C, ID="X_5", classes=["center", "incident"])
            X_83 = eval_trilinear_point(model, A, B, C, 'b*c/(b**(2) + c**(2))', ID="X_83", classes=["center", "incident"])
            central_line(model, X_5, X_83, 5, 83, incident=True)
            X_140 = eval_trilinear_point(model, A, B, C, '2*cos(A) + cos(B - C)', ID="X_140", classes=["center", "incident"])
            X_325 = eval_trilinear_point(model, A, B, C, '(csc(A))**(2)', ID="X_325", classes=["center", "incident"])
            central_line(model, X_140, X_325, 140, 325, incident=True)
            return promote_point_to_top(model, X_3398)


        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_3398 on the given reference triangle."""
            model = create_model('X_3398 = COS(A - 2ω) POINT')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_03398(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-03398.json"))
            write_center_svg(
                model_acute,
                here / "x-03398.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X3398¶

X₃₃₉₈¶