Is Secant the reciprocal of cosine?
In addition to sine, cosine, and tangent, there are three other trigonometric functions you need to know for the Math IIC: cosecant, secant, and cotangent. These functions are simply the reciprocals of sine, cosine, and tangent. Cotangent is the reciprocal of tangent.
Arccos definition. The arccosine of x is defined as the inverse cosine function of x when -1≤x≤1. (Here cos-1 x means the inverse cosine and does not mean cosine to the power of -1).
- Noun. 1. inverse cosine - the inverse function of the cosine; the angle that has a cosine equal to a given number. arc cosine, arccos, arccosine. circular function, trigonometric function - function of an angle expressed as a ratio of the length of the sides of right-angled triangle containing the angle.
- Sines and cosines for special common angles
Degrees Radians cosine 90° π/2 0 60° π/3 1/2 45° π/4 √2 / 2 30° π/6 √3 / 2
- The functions are usually abbreviated: sine (sin), cosine (cos), tangent (tan) cosecant (csc), secant (sec), and cotangent (cot). It is often simpler to memorize the the trig functions in terms of only sine and cosine: sin(q) = opp/hyp. csc(q) = 1/sin(q)
Updated: 2nd October 2019