About: Cos-1

Cos-1, COS-1, cos-1, or cos−1 may refer to: * Cos-1, one of two commonly used COS cell lines * cos x−1 = cos(x)−1 = −(1−cos(x)) = −ver(x) or negative versine of x, the additive inverse (or negation) of an old trigonometric function * cos−1y = cos−1(y), sometimes interpreted as arccos(y) or arccosine of y, the compositional inverse of the trigonometric function cosine (see below for ambiguity) * cos−1x = cos−1(x), sometimes interpreted as (cos(x))−1 = 1/cos(x) = sec(x) or secant of x, the multiplicative inverse (or reciprocal) of the trigonometric function cosine (see above for ambiguity) * cos x−1, sometimes interpreted as cos(x−1) = cos(1/x), the cosine of the multiplicative inverse (or reciprocal) of x (see below for ambiguity) * cos x−1, sometimes interpreted as (cos(x))−1 = 1/cos