Casio fx-350MS - Page 11

CHAPTER 1 Let’s Get Started
8
MODE
1
MODE MODE
1
3
=
SHIFT
cos
-
1
cos
0
•
8
˚’”
3
=
6
0
–
Ans
˚’”
Find all angles between °0 and °360 inclusive which satisfy the equation
38.0cos =x .
OPERATION
1. First make sure your calculator is in COMP/Deg mode.
2. Now, evaluate
38.0cos
1−
to determine α, the basic angle.
3. Press once and thus obtaining the basic angle
α as approximately '4067° .
4. To determine the second angle, which lies in the fourth quadrant, press
`
Therefore the solutions are
'4067° and '20292° , approximately.
Using similar operations as in Example 14, find all angles between °0 and °360 inclusive which
satisfy the equation
53.0cos =x .
cos
-1
0.38
67.66631734
Exam
p
le 14
D
0
cos
-1
0.38
67
– 39 – 58.74
360-Ans
292.3336827
360-Ans
292
– 20 – 1.26