Creating a Conic given 2 points, the chordal ratio and 2 tangency conditions

The 2 points and 2 tangents method of the Conic Curve command enables you to create a conic arc defined by its endpoints, its chordal ratio, and the tangency conditions at its endpoints. After specifying the endpoints, you can specify the tangency conditions by selecting existing lines, indicating points or using the specific handles. Then you can specify the chordal ratio.
As for the chordal ratio, please observe that values within specific ranges produce different types of curves:

Chordal ratio Type of curve 0 < ratio < 0.5 ellipse ratio = 0.5 parabola 0.5 < ratio <1 hyperbola

After starting the Conic Curve command, proceed as follows.

1	In the Type drop-down list, select 2 points and 2 tangents.
2	Specify the two endpoints of the conic arc by clicking or by using a snap command. To change the selected points, right-click on Points, select Reset in the context menu and specify the new points.
3	For each of the two endpoints, specify the tangency condition in one of the following ways: In the 1st Tangent and 2nd Tangent drop-down lists under Tangents Group, select the desired direction (see " How to define an axis or a line" for details). Use the handles: The three arc represent s the three angle s of revolution (about X, about Y, about Z). You can rotate the tangent vector about an axis by dragging the corresponding arc or by typing the value of the rotation into the Angle box which shows up when you pick the arc   The longest red line represents the tangent vector: you can pick its free endpoint and move it around in the space until you assign the tangent vector the desired direction.
4	In the Chordal Ratio box, type the value of the chordal ratio (0<ratio<0.5 ellipse; ratio=0.5 parabola; 0.5<ratio<1 hyperbola). In the following illustration we entered 0.8.
5	Click or to confirm your selections and create the curve. Click to discard your changes.