1. Use a calculator to evaluate sin(78o). Round your answer to 2 decimal places.
2. A 37.6 foot ladder just reaches the top of a building and forms an angle of 38.7owith the wall
of the building. How many feet tall is the building? Round your answer to the nearest foot and do
not write the units.
3. Find the exact value of sin(19).
4. Suppose that sec(t) = 3/2 and that t is in quadrant IV. Find the exact value of tan(t).
-3/2
?5?/2
5?/2
-2/3
None of these
5. Use the fact that the trigonometric functions are periodic to find the exact value of csc(1080)
-2
1
0
Undefined
6. If (a, b) is a point on the unit circle that corresponds to the angle t, then sin(t) equals:
a
b
-a
-b
none of these
7. A radio transmission tower is 435.1 feet tall. A guy wire is to be attached 6 feet from the top
and is to make an angle of 24.0o with the ground? How many feet long should the guy wire be?
Round your answer to the nearest foot (whole number) and do not write the units.
8. An angle with measure 4.0 radians is equal to how many degrees? Round your answer to 2
decimal places. Use 3.1416 as an approximation for pi.
9. In which quadrant does the angle t lie if cos(t) < 0 and csc(t) < 0?
I
II
III
IV
Can\'t be determined
10. If (a, b) is a point on the unit circle that corresponds to the angle t, then tan(t) equals:
a
b
a/b
b/a
a + b
None of these
11. sin(-t) equals which of the following?
cos(t)
sin(t)
-sin(t)
-cos(t)
Solution
1)0.98
2)29.3
3)0.1499
4)-sqrt(5)/2
5)Undefined
6)b
7)1055
8)229.18 deg
9)3rd quadarnt
10)b/a
11)-sint.
1. use fundamental identities to simply the expression cot tan .pdf
1. 1. use fundamental identities to simply the expression: cot ? tan ?
2. write the function in the terms of its cofunction of a complentary angle: tan pi/12
Solution
tank = 1/cotk
so tankcotk =1
b)cot(pi/2 - pi/12) =cot(5pi/12)
