Returns the inverse sine (arcsine) of a number.

Syntax

ASIN(<expN>)

<expN>

The sine of an angle, from –1 to +1.

Description

ASIN( ) returns the radian value of the angle whose sine is <expN>. ASIN( ) returns a number from –pi/2 to pi/2 radians. ASIN( ) returns zero when <expN> is 0. For values of x from –pi/2 to pi/2, ASIN(y) returns x if SIN(x) returns y.

To convert the returned radian value to degrees, use RTOD( ). For example, if the default number of decimal places is 2, ASIN(.5) returns .52 radians while RTOD(ASIN(.5)) returns 30.00 degrees.

Use SET DECIMALS to set the number of decimal places ASIN( ) displays.

To find the arccosecant of a value, use the arcsine of 1 divided by the value. For example, the arccosecant of 1.54 is ASIN(1/1.54), or .71 radians.