How do you use a calculator to evaluate cos^-1 0.24 in both radians and degree?

2 Answers
Jun 2, 2018

76.113@ and/or (76133pi)/180000

Explanation:

First i would get the degree by doing cos^-1(0.24) in a calculator to get 76.113@
This is 76.133 out of 360 which is 76.133/360
Radians is out of tau or 2pi To find out radian multiply the fraction by tau or 2pi to get:
76.133/360*2pi=(152.266pi)/360=(76133pi)/180000

Jun 3, 2018

x = 76^@, or (19pi)/45
x = 284^@, or (71pi)/45

Explanation:

cos ^-1 (0.24) --> arccos (0.24)
Calculator and unit circle give -->
cos x = 0.24 -->
arc x = +- 76^@
For (0, 360^@) the answers are:
x = 76^@ and
x = 284^@ (co-terminal to -76^@)
Convert to radians:
x = 76^@ --> x = (76 pi)/180 = (19pi)/45.
x = 284^@ --> x = (284pi)/180 = (71pi)/45