6.2 TRIGONOMETRIC FUNCTIONS: UNIT CIRCLE APPROACH
EXAMPLE 9 Using a Calculator to Approximate the Value of Trigonometric
Functions
Use a calculator to find the approximate value of:
(a)
o
48cos (c)
tan
SOLUTION (a) Set the MODE to degrees. This is done by pressing the
MODE button on the calculator. Now use the arrows to put the
cursor on Degree and press ENTER. You should have the output
shown in Figure 30(a). The trigonometric functions sine, cosine
and tangent are located in the middle of the keyboard:
Press the COS button, then press 4 8 ) . Hit ENTER to obtain
the results shown in Figure 30(b).
(b) Set the MODE to receive radians. Press the TAN button. Now
press
.
Tangent
by pressing
nd