# Is inverse cosine the same as Arccos?

**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).

A.

### 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.#### What is the reciprocal of the cosine function?

There are three reciprocal trigonometric functions, making a total of six including cosine,**sine**, and**tangent**. The reciprocal cosine function is**secant**: sec(theta)=1/cos(theta). The reciprocal**sine**function is**cosecant**, csc(theta)=1/**sin**(theta).#### What is tan equal to?

A convenient mnemonic for remembering the definition of the sine, cosine, and**tangent**is SOHCAHTOA (sine**equals**opposite over hypotenuse, cosine**equals**adjacent over hypotenuse,**tangent equals**opposite over adjacent). These geometrical objects are then called a**tangent**line or**tangent**plane, respectively.#### Is Secant the opposite of sine?

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.

Updated: 2nd October 2019