Condition for Two Tangents to Be Real

Condition for Two Tangents to Be Real

For the parabola:

$$y^2=4ax$$

two real tangents can be drawn from a point $$(x_1,y_1)$$ when the point lies outside the parabola.

$$y_1^2>4ax_1$$

Usage

- Used to determine whether two distinct real tangents can be drawn from a given point.