26 Part I: The Questions
157. Find the value of cos sin
−1 1
2
( )

 

  .
158. Find the value of tan cos
−1
3
2

 

 

 

  .
159. Find the value of csc arccos 4
5
(
) .
160. Find the value of sin tan
tan
−
−
+
1
1
2
3
( )
( )
(
) .
Solving Trigonometric
Equations Using Inverses
161–166 Solve the given trigonometric equation
using inverses. Find all solutions in the interval
[0, 2π].
161. sin x = 0.4
162. cos x = –0.78
154.
(A) f x
x
( )
cos
=
−
( ) −
2
1
2
4
1
π
(B) f x
x
( )
cos
= −
−
( ) +
2
1
2
4
1
π
(C) f x
x
( )
cos
= −
−
( ) −
2
4
1
π
(D) f x
x
( )
cos
= −
−
( ) −
2
1
2
4
1
π
(E) f x
x
( )
cos
= −
−
( ) −
2
4
4
1
π
Inverse Trigonometric
Function Basics
155–160 Evaluate the inverse trigonometric function
for the given value.
155. Find the value of sin
−1
3
2

 

  .
156. Find the value of arctan(–1).