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Chapter 3: Manual Calculations
If the base length of the right triangle is 505.8 feet, and the angle
of elevation is 36 degrees, then the following expression can be
derived:
the height of the Mendocino tree (ft.) = 505.8 ft. × tan(36°)
1. Verify/change the calculator’s angle unit.
2. Use the calculator’s trigonometric function key to enter/perform
the calculation.
1. Since the angle of elevation is measured in degrees, the
calculator’s angle setting will need to be matched with that.
Press
@
;
to bring
up the SETUP menu.
2. On the right side of the SETUP
menu, the current setup will
be displayed. Make sure that
the top line is indicated as
Deg (i.e., degrees). If not, then
the angle system will need
to be changed. Press
B
to select
B DRG, then press
1
to select
1 Deg.
3. Now, let’s work on the actual calculation part. Press the
#
key to enter the Calculation screen, and press
C
to clear
any screen entries.
2. Try it!
The Mendocino Tree, a coast redwood growing in Montgomery Woods State
Reserve in California, is known to be the tallest living tree in the world. You are to
find out how tall the tree is by using the following factors:
• The distance from you to the bottom of the
tree is exactly 505.8 feet, and the tree
stands vertically.
• The angle of elevation between the top
and the bottom of the tree is 36 degrees
CONCEPT
PROCEDURE