Secant line Secant line In geometry, a secant of a curve is a line that intersects the curve in at least two (distinct) points. The word "secant" comes from the Latin word "secare", meaning "to cut". In the case of a circle, a secant will intersect the circle in exactly two points and a chord is the line segment determined by these two points, that is the interval on a secant whose endpoints are these points. A straight line can intersect a circle in two, one or zero points. A line intersecting in two points is called a "secant line", in one
Area of a circle version of the divergence theorem), in a way that avoids all mention of trigonometry and the constant . Consider the vector field formula_27 in the plane. So the divergence of r is equal to two, and hence the area of a disc "D" is equal to By Green's theorem, this is the same as the outward flux of r across the circle bounding "D": where n is the unit normal and "ds" is the arc length measure. For a circle of radius "R" centered at the origin, we have formula_30 and formula_31, so the above equality is The integral of