Sec-1

Sec-1, SEC-1, sec-1, or sec&minus;1 may refer to:


 * sec x&minus;1 = sec(x)&minus;1 = exsec(x) or exsecant of x, an old trigonometric function
 * sec&minus;1y = sec&minus;1(y), sometimes interpreted as arcsec(y) or arcsecant of y, the compositional inverse of the trigonometric function secant (see below for ambiguity)
 * sec&minus;1x = sec&minus;1(x), sometimes interpreted as (sec(x))&minus;1 = $1⁄sec(x)$ = cos(x) or cosine of x, the multiplicative inverse (or reciprocal) of the trigonometric function secant (see above for ambiguity)
 * sec x&minus;1, sometimes interpreted as sec(x&minus;1) = sec($1⁄x$), the secant of the multiplicative inverse (or reciprocal) of x (see below for ambiguity)
 * secx&minus;1, sometimes interpreted as (sec(x))&minus;1 = $1⁄sec(x)$ = cos(x) or cosine of x, the multiplicative inverse (or reciprocal) of the trigonometric function secant (see above for ambiguity)