Trigonometric functions
posted by Jon .
1)Which angle is coterminal with a 400 degree angle in standard postion?
A)40
B)80
C)320
D)400
I chose A
(for the next one I don't know what its called but it looks like 0 with a horizontal line through the middle.)
2)Find the exact value of cos looks like 0 with a horizontal line through the middle if the terminal side of 0 with a horizontal line through the middle in standard postion contains the point (6,8).
A)4/5
B)3/5
C)4/5
D)3/5
I chose B

plus or minus all the way around or 360 changes nothing, so add 360 first
400 + 360 = 40
well usually standard is counterclockwise from the x axis so
40 = 360 40 = 320
I would choose C
2,
That is called THETA but I will call it T
It is in the fourth quadrant between 270 and 360
the hypotenuse of this 3,4,5 triangle = 2*5 = 10
the cosine = adjacent/hypotenuse = +6/10==+3/5
B = agree 
C for the first one. All of them aside from 320 lie in Quadrant 1. 320 and 400 lie in Quadrant 4. Since 400 is negative it moves clockwise, when the other angles move counterclockwise.
I'm not sure what you're asking in the 2nd. The exact value of cos theta with a horizontal line through the middle of the angle? 
Remember a negative angle is a clockwise rotation, so a 400º angle goes all the way around and down another 40º into the fourth quadrant.
Using the standard notation that would be an angle of 320º
for your second question you are probably looking at cosθ, or cos theta.
Theta is often used as the variable to represent an angle and is one of the Greek letters.
So draw a triangle by joining the origin to the point (6,8), which is the fourth quadrant
cosθ = adjacent/hypotenuse
hypotenuse = √(6^2 + (8)^2) = 10
adjacent = 6
so cosθ = 6/10 = 3/5
Respond to this Question
Similar Questions

Trigonometric functions
1)I have a right triangle. the hypotenuse is 7 the opposite leg is x and an angle is 32. Which equation can be used to find x? 
Algebra II
1)Rewrite 5pi/4 radians in degree measure. Answer: 225 2) Which angle is coterminal with a 400 degree angle in standard position? 
math
Find an angle between 0 degree and 360 degree that is coterminal with given angle. a. 361 degree b. 100 degree c. 1270 degree 
Math Trigonometry
The point, in on the terminal side of an angle in standard position find the exact value of the six trigonometric functions of the angle a. (8,15) b.(9,40) 
math
I put the wrong angle measure on my earlier question. It should have been... How many different triangles, if any, can be drawn with on 20 degree angle, one 45 degree angle, and one 115 degree angle. Thanks.... 
Trigonometry (Coterminal Angles)
What is the SMALLEST POSITIVE ANGLE that is coterminal with the angle having the radian measure of 10π/3? 
trigonometric oblique triangle
a flagpole at a right angle to the hrizontal is located on a slope that makes an angle of 14 degree with the horizontal the flagpole casts a 16m shadow up the slope wen the angle of elevation from the tip of the shawdow to the sun … 
Algebra
Determine the measure of each exterior angle. The triangle looks like an upside down A with one line running longer at the point. The inside angles are A 50 and in the next corner 75. In the bottom of the Aletter I need to solve … 
Math2
Demi would like to estimate the height of the hill from its base. Using a compass, she found that the angle between C and B, from A, was 80 degrees. She also estimated the angle from horizontal to the summit to be 23 degrees. She then … 
Functions (Math)
The point P(2, 5) is located on the terminal arm of an angle θ in standard position. a) Draw and label an appropriate diagram. Remember to label θ and all the sides of the triangle. b) Determine the exact values of the primary trigonometric …