HP HP-67

98 Function Keys
Solution: Convert all degrees, minutes, seconds entries into decimal
degrees as you key them in. The equation for the great circle distance
from Tristan da Cunha to the nearest inhabited land is:
Distance = cos™! [sin (37°03") sin (15°55") + cos (37°03")
cos (15°55") cos (5°43' — 12°18")] X 60
Press Display
D
5.43 0 (3 5.72
12.18 [0 (9 &2
o
15.55 0 (3 1[ 15.92
37.03@E ER 0 37.05
@3 (cos 0.80
B 00 GEH
310G
o=
60 B3
Selects degrees mode.
(Display assumes no
results remain from
previous examples.)
Distance in nautical
miles that Odysseus must
sail to visit Penelope.
Polar/Rectangular Coordinate Conversion
Two functions are provided for polar/rectangular coordinate
conversions. Angle 6 is assumed in decimal degrees, radians, or
grads, depending upon the trigonometric mode first selected by
[EG], [RAD], or (GRD).