# trig

Popular questions
1. ## trig

A survey team is trying to estimate the height of a mountain above a level plain. From one point on the plain, they observe that the angle of elevation to the top of the mountain is 24. From a point 1000 feet closer to the mountain along the plain, they

asked by Anonymous on October 10, 2012
2. ## trig

What are the coordinates of the terminal point determined by t=7pi/6 ?

asked by BreAnne on January 27, 2012
3. ## trig

prove that cos 52 + cos 68 + cos172 = 0

asked by Anonymous on October 17, 2010
4. ## trig

if 5sin theta + 12cos theta is equal to 13 find the value of tan theta

asked by Anonymous on June 15, 2013
5. ## Trig

How can I find the exact value of Sin 480 degrees? Thanks

asked by Rachal on May 12, 2011
6. ## trig

Find all angles θ between 0° and 180° satisfying the given equation. (Enter your answers as a comma-separated list. Round your answers to one decimal place.) cos θ = 1/7

asked by stellar on September 30, 2011
7. ## trig

verify the identity: sin(x+y)-sin(x-y)=2cosx siny

asked by stacey graham on March 26, 2010
8. ## trig

A tree on a hillside casts a shadow c ft down the hill. If the angle of inclination of the hillside is b to the horizontal and the angle of elevation of the sun is a, find the height of the tree. Assume a = 48°, b = 18° c = 235 ft. (Round your answer to

asked by Anonymous on November 29, 2012
9. ## Trig

I need help setting these up. 1.) Use the parallelogram rule to find the magnitude of the resultant force for the two forces shown in the figure. round to one decimal place. Theta= 35 degree, b=98 lbs, c=55lb 2.) Find the magnitude and direction angle for

asked by Derrick on November 26, 2014
10. ## Trig

Verify the identity. cos 4x + cos 2x = 2 - 2 sin^2(2x) - 2 sin^2 x

asked by Mitchel on February 17, 2013
11. ## trig

half angle formula to find exact value cos 112.5 degree

asked by Billy on March 8, 2016
12. ## trig

If (m+2)sin ø + (2m-1)cos ø = 2m+1 then tan ø is equal to

asked by amit on May 29, 2013
13. ## trig

find sin theta and tan theta if cos theta = 2/3 and cot theta is >0 and find cos theta and cot theta if sin theta = 1/3 and tan theta is

asked by skye on July 26, 2012
14. ## Trig

Find the point on the terminal side of θ = three pi divided by four that has a y coordinate of 1. Show your work for full credit.

asked by Mitchel on January 20, 2013
15. ## Trig

A railroad tunnel is shaped like semi-ellipse. The height of the tunnel at the center is 69 ft and the vertical clearance must be 23 ft at a point 16ft from the center. Find an equation for the ellipse.

asked by Stacey grahaM on May 2, 2010
16. ## trig

A woman standing on a hill sees a flagpole that she knows is 65 ft tall. The angle of depression to the bottom of the pole is 14°, and the angle of elevation to the top of the pole is 18°. Find her distance x from the pole. (Round your answer to one

asked by Dominic on September 21, 2011
17. ## trig

To guard against a fall, a ladder should make an angle of 75o or less with the ground. What is the maximum height that a 20-foot ladder can reach safely to the nearest tenth of a foot? in my diagram I set it up using the sin function since I want to find

asked by Anonymous on June 2, 2014
18. ## trig

Given sin a = 15/17 with a in Quadrant I and cos beta = 4/5 with beta in QuandrantIV, find the exact value of cos(a+beta)

asked by MIK on May 17, 2012
19. ## trig

A plane has an airspeed of 200 miles per hour and a heading of 28.0°. The ground speed of the plane is 207 miles per hour, and its true course is in the direction of 38.0°. Find the speed and direction of the air currents, assuming they are constants.

asked by bryan on November 29, 2012
20. ## trig

How do you find the exact value of sin 5pi/8?

asked by Sierra on November 7, 2012
21. ## Trig

Find sin(s+t) and (s-t) if cos(s)= 1/5 and sin(t) = 3/5 and s and t are in quadrant 1. =Sin(s)cos(t) + Cos(s)Sin(t) =Sin(1/5)Cos(3/5) + Cos(-1/5)Sin(3/5) = 0.389418 Sin(s-t) =sin(s)cos(t) - cos(s)sin(t) =sin(-3/5)cos(1/5) - cos(1/5)sin(3/5) =Sin-3/5

asked by Sally on May 7, 2015
22. ## trig

It is 4.7km from Lighthouse A to Port B. The bearing of the port from the lighthouse is N73E. A ship has sailed due west from the port and its bearing from the lighthouse is N31E. How far has the ship sailed from the port?

asked by Ashley on November 18, 2012
23. ## trig

Solve for sin4x=sin2x?

asked by Anonymous on March 7, 2016
24. ## Trig

From two different tracking stations, a weather balloon is spotted from two angles of elevation, 57degrees and 83 degrees, respectively. The tracking stations are 15 km apart. Find that altitude of the balloon. Any help given will be greatly appriciated

asked by Sonia on July 20, 2010
25. ## Trig

The postal service places a limit of 84 inches on the combined lenght and girth (distance around) of a package to be sen parcel post. What Dimensions of a rectangular box with square cross-section will contain the largest volume that can be mailed?

asked by Meg on May 12, 2013
26. ## trig

a hedgehog wishes to cross a road without being run over. he observes the angle of elevation of a lamp post on the other side of the road to be 27 degrees from the edge of the road and 15 degrees from a point 10m back from the raod. How wide is the road??

asked by Fiona on October 16, 2010
27. ## trig

cos/sin use 2npi and tan uses npi, but how do you know when to add 2npi or npi to the solution of the equation?

asked by Anonymous on March 19, 2014
28. ## trig

The captain of a ship at sea sights a lighthouse which is 120 feet tall. The captain measures the the angle of elevation to the top of the lighthouse to be 19 ^\circ. How far is the ship from the base of the lighthouse?

asked by Dan on October 1, 2011
29. ## trig

ABC is rightangled triangle. AD is the bisector of angle BAC. Angle DAC=15 degrees. X=CD. Find X. I know the answer is 7.1 but do not know how to do the actual sum. Can you please help AB = 23 CM

asked by jane on May 5, 2011
30. ## trig

A certain species of tree grows an average of 0.5 cm per week. Write an equation for the sequence that represents the weekly height of this tree in centimeters if the measurements begin when the tree is 800 centimeters tall?

asked by mia on June 28, 2012
31. ## Trig

A weight is oscillating on the end of a spring. The position of the weight relative to the point of equilibrium is given by y=1/12(cos8t-3sin8t), where y is the displacement (in meters) and t is the time (in seconds). Find the times when the weight is at

asked by Nicole on October 27, 2014
32. ## Trig

Cosine theta=8/17 and 270 degrees is < theta, and theta is< 360

asked by Sarah on September 28, 2016
33. ## Trig

Find all solutions of the equation in the interval [0,2pi). 2sin theta+1=0. Write answer in radians in terms of pi.

asked by James on August 19, 2015
34. ## trig

A road has a 10% grade (slope). To the nearest degree what is the angle of elevation of the road?

asked by Lake on July 14, 2015
35. ## trig

How do I find the exact value of sin (pi/24)?

asked by Luis on March 17, 2013
36. ## trig

sin2x=cos3x then sinx=?(if 0

37. ## Trig

Find the approximate value of cot θ​, given that csc θequals=3.5891420 and θ is in quadrant I.

asked by Ashley on January 26, 2017
38. ## trig

Two ships, one sailing at 30 km/hr and the other at 45 km/hr, left port at the same time. Three hours later they were 120 km apart. If you had to find the angle between their courses an equation that could be used to solve this problem is:

asked by jonathan on February 24, 2008
39. ## trig

Observers at P and Q are located on the side of a hill that is inclined 32° to the horizontal, as shown. The observer at P determines the angle of elevation to a hot-air balloon to be 56°. At the same instant the observer at Q measures the angle of

asked by e on December 5, 2019
40. ## Trig

A railroad tunnel is shaped like a semiellipse as shown below. A semiellipse is shown on the coordinate plane with vertices on the x axis and one point of intersection with the positive y axis. The height of the tunnel at the center is 27 ft and the

asked by Lisa on September 27, 2014
41. ## Trig

If you are dealt 3 cards from a shuffled deck of 52 cards, find the probability that all 3 cards are picture cards.

asked by Katie on May 7, 2012
42. ## Trig

a smokestack is 190 feet high. a guy wire must be fastened to the stack 30.0 feet from the top. the guy wire makes an angle of 39.0deg with the ground. find the length of the guy wire

asked by Struggler in math on October 21, 2015
43. ## Trig

As you ride a ferris wheel, your distance from the ground varies sinusoidally with time. When the last passenger boards the ferris wheel and the ride starts moving, let your position be modeled by the diagram provided. Let t be the number of seconds that

asked by TRig on March 22, 2012
44. ## trig

What is the projection of (2,6) onto (-1,5)?

asked by BT on March 4, 2010
45. ## Trig

Find the length of a chord intercepted by a central angle of 25 degrees in a circle of radius 30 feet

asked by Anonymous on April 6, 2016
46. ## trig

Angle θ lies in the second quadrant, and sin θ = 3/5. Find cos θ and tan θ.

asked by Britt on April 1, 2016
47. ## trig

what is terminal point of 5pi/4?

asked by KLL on July 28, 2015
48. ## trig

From the top of a tower of height 75m, a man sees two goats, both due west of him. If the angles of depression of the two goats are 10 degrees and 17 degrees, calculate the distance between them. It wants the angle of depression. I , myself, don't

asked by Anonymous on November 17, 2014
49. ## Trig

Find the exact value of tan 5pi/12 using the half-angle identity.

asked by Cynthia on October 15, 2011
50. ## trig

A tunnel for a new highway is to be cut through a mountain that is 260 feet high. At a distance of 200 feet from the base of the mountain, the angle of elevation is 36 degrees. From a distance of 150 feet on the other side of the mountain, the angle of

asked by Marie on June 5, 2012
51. ## trig

find exact value using sum or differnce equations. tan(19pi/12)

asked by chris on November 18, 2010
52. ## trig

Find value of tan75/2

asked by Ram on October 21, 2011
53. ## trig

Given that tan B= 7/24 with B in quadrant III, find sin 2B, cos 2B, and tan 2B, using angle identities.

asked by Ryan on October 11, 2011
54. ## trig

Let (theta) be an angle in quadrant II such that csc(theta)=8/5 Find the exact value of tan(theta) and cos(theta).

asked by andy on May 10, 2011
55. ## Trig

Which trigonometric function can equal or be greater than 1.000? A Sine B Cosine C Tangent D none of the above

asked by Carl on December 13, 2011
56. ## Trig

1. Given Sin(A) = ⅗ and Cos(B) = 8/17 in Quadrant I, find Sin(A+B). a) 24/80 [b)] 84/85 c) 60/80 d) 60/85 Find Cos(A+B). a) 32/80 b) -45/85 c) -13/80 [d)] -13/85 Find Tan(A+B) a) 0.8 [b)] -1.72 c) -4.21 d) -6.46 I keep getting an 1.61 answer but that

asked by Lyss on September 6, 2016
57. ## trig

what is the exact value of tan 105 degrees

asked by fortue on June 29, 2016
58. ## trig

Find the exact value by using a half-angle identity. cos 22.5 degrees

asked by Omar on October 11, 2011
59. ## trig

A pilot is flying over a straight highway. He determines the angles of depression to two mileposts, 4 mi apart, to be x = 27° and y = 53°, as shown in the figure. (Round your answers to two decimal places.) (a) Find the distance of the plane from point

asked by stellar on September 30, 2011
60. ## trig

Find sin(2theta) if tan of theta = 7/24, pi < theta < 3pi/2 ?

asked by Anonymous on August 9, 2011
61. ## trig

Given that tan 45=1, use tan(x+y) to show that tan 22.5= /2 - 1. (/is square root sign

asked by Mimi on August 24, 2010
62. ## trig

the voltage, v, in volts, applied to an electric circuit can be modelled by the equation v=167sin(120pi)(t), where t is the time, in seconds. A component in the circuit can safely withstand a voltage of more than 120 V for 0.01 sec or less. a) determine

asked by Anonymous on April 27, 2009
63. ## trig

a ferris wheel with a radius of 14m makes one revolution every 30 seconds. the bottom of the wheel is 2.5m above the ground. a) find the equation b) how does the equation change if the graph starts at the centre of rotation

asked by sandy on December 9, 2018
64. ## trig

The terminal side of θ lies on a given line in the specified quadrant. Find the values of the six trigonometric functions of θ by finding a point on the line. Line: (55/48)x Quadrant:III sin(θ)= cos(θ)= tan(θ)= csc(θ)= sec(θ)= cot(θ)=

asked by andrea on January 31, 2012
65. ## trig

If θ is an angle in standard position and its terminal side passes through the point (20,-21), find the exact value of sec(θ).

asked by Anonymous on December 9, 2011
66. ## Trig

How do you convert rectangular equations into polar equations? If x4−y4=xy , then r2=atan(b); What is a? What is b?

asked by Audrey on December 13, 2010
67. ## trig

Which expression is equivalent to tan(-x)cos^2x? -sin xcos x sin xcos x tan x + sin2x tan x − sin2x -tan x − sin2x

asked by jimmy on March 31, 2016
68. ## trig

A spring is attached to the ceiling and pulled 17 cm down from equilibrium and released. After 3 seconds the amplitude has decreased to 16 cm. The spring oscillates 13 times each second. Assume that the amplitude is decreasing exponentially. Find an

asked by Tricia on August 17, 2014
69. ## Trig

Use the half-angle formulas to come up with an exact expression for each function value below. You do not have to simplify your answers. cos(pi/16)

asked by Help on April 1, 2012
70. ## trig

find the exact value of sin(u+v) given that sin u=3/5 and sin v= 15/17

asked by k on December 18, 2011
71. ## trig

find exact value of cos(23pi/6)

asked by shaili on August 9, 2010
72. ## Trig

Find all the solutions in the interval [0,2pi). 2sin2x - sqrt(2) = 0 sin2x = sqrt(2)/2 I'm confused by the double angle. Please help.

asked by Travis on December 2, 2008
73. ## trig

A gear with a radius of 32 centimeters is turning at pi/9 radians/sec. What is the linear speed (velocity) at a point on the outer edge of the gear?

asked by Chris on March 15, 2015
74. ## Trig

A 16 - foot ladder leaning against the side of a house reaches 12 feet up the side of the house. What angle does the ladder make with the ground

asked by Bri on September 23, 2012
75. ## trig

Solve for x if sin2x=cos(x+60 and x€ [-90,180].show all work details

76. ## Trig

sinAsin2A+sin3Asin6A+sin4Asin13A/sinAcos2A+sin3Acos6A+sin4Acos13A = tan9A

asked by Kewal on January 2, 2012
77. ## trig

in a circle of radius 26, find the length of the arc spanned by a central angle of pi/4 radians. round your answer to 2 decimal places. use 3.1416 as an approx for pi.

asked by tiana on October 5, 2011
78. ## Trig

Two ships leave a harbor at the same time. One ship travels on a bearing S11 degrees W at 12 mph. The second ship travels on a bearing N75 degrees E at 9 mph. How far apart will the ships be after 3 hours?

asked by Erin on June 29, 2018
79. ## trig

How do you solve sin(e^x)=0 for x? The question is "find the smallest number x such that sin(e^x)=0".... but I can't even get AN answer lol! Much appreciated!

asked by Luna on September 11, 2013
80. ## trig

Use a table of trigonometric values to find the angle θ in the right triangle in the following problem. Round to the nearest degree, if necessary. cos θ = 0.9659 A = ? H = 20

asked by ab on January 16, 2013
81. ## Trig

Find the co terminal angle for 15pi/4

asked by Jenn on April 7, 2012
82. ## trig

-Find sin(x+y), cos(x-y), tan(x+y) and the quadrant of x+y sinx=-3/5, cosy=-7/25, x and y in Q3

asked by Dana on November 16, 2011
83. ## trig

use a half angle formula to find the exact value of cos 75 degree

asked by lan on May 8, 2011
84. ## trig

simplify cos(30+x)+cos(30-x)

asked by Anonymous on December 11, 2010
85. ## trig

The average depth of water at the end of a dock is 6 ft. This varies 2 ft in both directions with the ride. Suppose there is a high tide at 4 am. If the tide goes from low to high every 6 hours, write a cosine function describing the depth of the water as

asked by ske on May 4, 2009
86. ## Trig

A road has a grade (slope) of 15%. What is the angle of elevation of the road, to the nearest degree?

asked by Ash on March 18, 2019
87. ## trig

evaluate the expression under the given conditions tan 2 theta; cos theta=7/25, theta in quadrant I

asked by Anonymous on July 9, 2014
88. ## trig

use a half-angle identity to find the exact value of tan 105 degrees.

asked by Karen on July 22, 2013
89. ## trig

what is the reference angle for 17 pi/12?

asked by Brandon on August 23, 2011
90. ## Trig

The angle 2x lies in the fourth quadrant such that cos2x=8/17. 1.Which quadrant contains angle x? 2. Determine an exact value for cosx 3. What is the measure of x in radians? ---------------- I know that quadrant 4 has 2x in it, so quadrant _____ has to

asked by Halle on May 31, 2009
91. ## Trig

Use the half angle formula to find the exact value of tan 7 pie/8

asked by Kay on September 13, 2007
92. ## Trig

Find sin2theta, cos2theta, and tan2theta for costheta = -12/13 in pi < theta < 3pi/2. My answers: 20111/24336 for tan2theta. 144/169 for cos2theta -120/338 for sin2theta

asked by Anonymous on May 20, 2015
93. ## trig

An airplane is traveling at a speed of 724 km per hour at a bearing of N30°E. If the wind velocity is 32 km per hour from the west, find the resultant speed and direction of the plane.

asked by Lin on February 23, 2015
94. ## Trig

Write a quadratic equation whose roots are 5 + i radical 2 and 5 – i radical 2 ____ x^2 + _____ x+ ______=0

asked by Kiki on April 26, 2014
95. ## trig

sec0+ten0-1/tan0+sec0+1=1+sin0/cos0

asked by rahul on February 24, 2013
96. ## trig

A ship is headed due north at a constant 20 miles per hour. Because of the ocean current, the true course of the ship is 15°. If the currents are a constant 18 miles per hour, in what direction are the currents running? (Enter your answers as a

asked by janice on November 16, 2012
97. ## Trig

prove (cscx-secx/cscx+secx)=(cotx-1/cotx+1)

asked by Bud on March 3, 2012
98. ## trig

A pendulum is 18 feet long. Its central angle is 44º. The pendulum makes one back and forth swing every 12 seconds. Each minute, the pendulum swings _____ feet. (Answer to the nearest foot.)

asked by ahnas on June 14, 2012
99. ## trig

An airplane has an airspeed of 450 km/hr bearing N45E. The wind velocity is 30 km/hr in the direction N30W. What is the ground speed and what is its direction?. I have gotten this far: A= 450cos(45), 450sin(45) = (318.20, 318.20) W= 30cos(120), 30sin(120)

asked by VEJ on July 13, 2011
100. ## trig

please help me. use trig. identities to find the exact value. tan 25° + tan 5° / 1- tan 25° tan 5°

asked by ann on April 30, 2010