Casio fx-350MS Booklet

CHAPTER 8 Angles of Elevation and Depression
22
2
=
5
7
SHIFT
tan
-
1
tan
5
2
a
b
/
c
=
2
4
0
X
¡
sin
sin
7
5
5
0
=
SHIFT
tan
-
1
tan
5
2
a
b
/
c
Ans
Three points N, Y and W are at sea level. Y is the foot of a vertical
lighthouse. N is 257m due north of Y and W is due west of Y. The height
of the light house is 52m.
(a) Calculate the angle of elevation of X from N.
(b) The bearing of W from N is 040°. Calculate the distance YW.
(c) Calculate the angle of elevation of X from W.
OPERATION
1. Find the angle of elevation by using
257
52
tan =∠XNY . Make sure your calculator is in
COMP/Deg mode.
The angle of elevation of X from N is approximately 11.44°.
2. Use the formula
°
=
° 50sin
257
40sin
YW
to find the distance YW.
YW is approximately 215.65m.
3. Perform this calculation right after step 2. Using
YW
XWY
52
tan =∠
, press
Hence, the angle of elevation of X from W is approximately 13.56°.
Exam
p
le 2
tan
-1
52ª257
11.4384942
2
Y
X
W
N
257Xsin 40¡sin 50
215.648605
2
N
Y
W
40°
50°
tan
-1
52ªAns
13.557099
3

Casio fx-350MS Specifications

General

Type	Scientific
Form factor	Pocket
Power source	Battery

Weight and Dimensions

Weight	100 g
Dimensions (WxDxH)	12.2 x 85 x 155 mm