41. Quasi-Newton methods are generalizations of the secant method to find the root of the first derivative for multidimensional problems. 42. The tangent at a point on a curve is defined intuitively as the limiting position of secant line through the point. 43. If you start with a secant , and move the two points closer together, the secant will become a tangent. 44. If you start with a secant, and move the two points closer together, the secant will become a tangent. 45. Where sech is the hyperbolic secant function and \ delta is a phase shift ( by an initial horizontal displacement ). 46. As a point " q " approaches the origin from the right, the secant line always has slope 1. 47. Play piercing as part of a BDSM secant so that both ends are accessible, rather than'into'the skin. 48. The secant , ellipsoidal form of the transverse Mercator is the most widely applied of all projections for accurate large scale maps. 49. If the initial values are not close enough to the root, then there is no guarantee that the secant method converges. 50. Furthermore, Brent's method uses inverse quadratic interpolation instead of linear interpolation ( as used by the secant method ).