Angle ∠BAC might refer to any of four angles: the clockwise angle from B to C, the anticlockwise angle from B to C, the clockwise angle from C to B, or the anticlockwise angle from C to B, where the direction in which the angle is measured determines its sign (see Positive and negative angles). However, in many geometrical situations it is obvious from context that the positive angle less than or equal to 180 degrees is meant, and no ambiguity arises. Otherwise, a convention may be adopted so that ∠BAC always refers to the anticlockwise (positive) angle from B to
Hyperbolic angle identities use the number "i" to remove the alternating factor (−1) from terms of the series to restore the full halves of the exponential series. Nevertheless, in the theory of holomorphic functions, the hyperbolic sine and cosine functions are incorporated into the complex sine and cosine functions. Hyperbolic angle In mathematics, a hyperbolic angle is a geometric figure that defines a section of a hyperbola. The relationship of a hyperbolic angle to a hyperbola parallels the relationship of an "ordinary" angle to a circle. Hyperbolic angle is defined in terms of the "standard" rectangular hyperbola: "y" = 1/"x", for positive