Practice Exercises
1. For each of the following angles, find a positive angle of
less than one revolution that is co-terminal with the given
angle.
A. 500°
B. -900°
2. Find the reference angle for the angle 320°.
3. Evaluate the expression Arccos (-2).
4. Use the fundamental identities to write the expression cot
x tan² x in terms of one trigonometric function or
a constant.
5. Prove that the equation sin³ x = sin x cos²
x is an identity.
6. Evaluate the expression cos 950° cos 550° - sin 950° sin 550°
by reducing it to a function of a single form.
7. What is the value of x in the interval 90 <
x < 180° that satisfies the equation sin
x + sin² x = 0?
A. 90°
B. 135°
C. 180°
D. 270°
8. Find the area of the triangle with the following
measurements:
b = 14, c = 5, A = 30.
9. Determine all of the missing parts of the triangle from the
information given:
A = 50°, C = 33.5°, b = 76
10. A child's kite is caught in the top branches of a tree. If
the 120 floor kite string makes an angle of 28° with the ground,
what is the approximate height of the tree?
