Intro to Trigonometry
Name___________________
Unit 1A Task #2
Date________Period _______
1.) Through how many radians does the minute hand of a
clock turn from 2:30 P.M. until 2:55 P.M ?
2.) Find the radian measure as a multiple of  of the angle
made by clock hands positioned at 9:25. Assume the hour
hand is exactly on 9.
If you rotate a clock face 90° clockwise, the hands will form an angle in standard
position, with the initial side going from the center of the clock face to the number 12.
3.) What angle do the clock hands form at 7 o’clock? Write the six trigonometric functions for
this angle.
4.) In this example, where is the x-axis? What is the reference angle for the angle formed at 4
o’clock?
5.) Imagine the clock hands moving backward from 7 o’clock to 4 o’clock. Through what
angle does the hour hand move? Give your answer in degrees. Write the six trigonometric
functions for this angle.
6.) Through what angle does the minute hand travel in 100 minutes? Give your answer in
radians. Find the reference angle, then write the six trigonometric functions.
Study the diagram. You are with a group
of hikers heading from the parking lot to
the campground. The park ranger tells the
1
group that the cosine of angle is .
2
1
? How could you
2
find the sine and tangent of this angle? There are six trigonometric functions in all. How are
they defined?
7.) How do you know that the cosine of angle θ in the park diagram is
8.) Which of the special angles have a cosine with this value? Why is it possible to write exact
values for the trigonometric functions of the special angles?
9.) A compass bearing is an angle of rotation starting from north and going clockwise. For
example, a heading straight east is 90°. Use this information to find the compass heading from
the park to the campground. How can you find the six trigonometric functions for this angle?