Arc Trigonometric Functions - Sharp EL-W531X Operation Manual

Arc Trigonometric Functions

Arc trigonometric functions, the inverse of trigonomet-
ric functions, are used to determine an angle from ratios
of a right triangle. The combinations of the three sides
are sin , cos , and tan
-1 -1
(arc sine) Determines an angle based on the ratio
b/a of two sides of a right triangle.
(arc cosine) Determines an angle based on the ratio
c/a for two sides of a right triangle.
(arc tangent) Determines an angle based on the
ratio b/c for two sides of a right triangle.
<Example 1>
At what angle should an airplane climb in order
to climb 80 meters in 100 meters?
[DEG mode]
. Their relations are;
-1
Operation
80
100
Display
43
a
θ
c
b
θ
= sin
-1
a
c
θ
= cos
-1
a
b
θ
= tan
-1
c
b