trigonometry

2,056 results, page 18

maths trigonometry

sin (60 degrees + theta)-cos(30 degrees - theta)is equal to (A)2 cos theta (B)2 sin theta (C)theta (D)1 could u plz explain this answer thank you

trigonometry

can you correct the rest for me please? Express each as a function of theta: a. sin (270deg + theta)= cos theta b. cos (pi + theta)= -cos theta c. tan (810 + theta)= ????? d. sin (theta - 180)= -sin theta

trigonometry

can you correct the rest for me please? Express each as a function of theta: a. sin (270deg + theta)= cos theta b. cos (pi + theta)= -cos theta c. tan (810 + theta)= ????? d. sin (theta - 180)= -sin theta

trigonometry

tanθ= -2sqrt10/3 and π/2<θ< π find a. cos(-θ) b. cos(11π/6 - θ) c.sin2θ d.tanθ/2 can some please explain to me how to solve these questions? thanks

Math-Trigonometry

12) Two jeeps in the desert leave their starting points at noon. The first travels a course of 345º and averages 23 mph. The second travels a course of 45º and averages 20 mph. How far apart are the two jeeps at 10 PM? What is the bearing from the first jeep to the second at...

algebra and trigonometry

At a college function, a total of 180 tickets were sold. The tickets were priced at $5, $10, and $15, and the money collected that day was $1,900. The sum of the numbers of $5 and $15 tickets sold was twice the number of $10 tickets sold. Find the number of each type of ticket...

trigonometry

a surveyor 1standing on a highway observed the angle of elevation of the airplain as 22.5°. at the same time, a surveyor 2 observed the angle of elevation of the same airplane to be 30°. if the airplane was 850m directly above a point on the highway, find the distance ...

Trigonometry

Does it make a difference whether you translate a graph first and the scale the image, or scale the graph first and then translate the image?

Trigonometry

Suppose sin A = 12/13 with 90º≤A≤180º. Suppose also that sin B = -7/25 with -90º≤B≤0º. Find tan (A – B).

Trigonometry

The Earth rotates on it's axis once every 24 hours. a)How long does it take Earth to rotate through an angle of 4pi/3? b)How long does it take Earth to rotate through an angle of 210 degrees?

trigonometry

how to express radians to degrees, minutes, and seconds? how to express fractions to degrees, minutes, and seconds? through how many radians does the hour hand of a watch turn in 5 hours? 1/2 hour? 10 minutes? 3 days? between 8 am and 5:30 pm?

Trigonometry

a skater skates along a straigh path from point A to point . Two streets that intersect a point C also intersect the path at points A and B. Street AC is 0.4 miles and street BC is 1.3 miles. The included angles at c is 107 . How far did the skater skate from point A to B

Science Question 1

Having nothing to do with trigonometry, what type of parallaxes use the width of absorption lines to estimate the star's luminosity and size and distance? A.bolometric B.photometric C.spectroscopic D.holographic E.video metric http://en.wikipedia.org/wiki/...

trigonometry

a surveyor finds that from Point A on the ground the angle of elevation to the top of a mountin is 23 degrees. when he is at point B that is 1/4 closer to the base of the mountain the angle of elevation is 43 degrees. how high is the moutnain? One mile =5280 feet. (Assume that...

Trigonometry

A communications tower is located at the top of a steep hill, as shown. The angle of inclination of the hill is 58°. A guy wire is to be attached to the top of the tower and to the ground, 50 m downhill from the base of the tower. The angle α in the figure is determined ...

Trigonometry

A lean-to is a simple shelter with three walls, a sloping roof, and an open front facing away from the prevailing winds. The back wall is short compared to the front opening. If the lean-to at a campsite has a front opening that is 7.0 ft tall, a back wall that is 2.0 ft tall...

trigonometry

A plane flies due south from an airport for 92 miles, and then turns and goes S63°W for 50 miles. How far is the plane from the airport (to the nearest tenth of a mile)? What direction is the plane from the airport (to the nearest tenth of a degree)? (That is, find the ...

Trigonometry

A clown is juggling at a circus. The path of a ball is given by the parametric equations x=2 cos T + 2 and y = 3 sin T + 3. In what direction is the ball moving? Up and to the right counterclockwise down and to the right clockwise After graphing it and observing its ...

TRIGONOMETRY

Can you please help me with this question on my study guide for my trig final? Thanks! I'd also appreciate if you can check out my other postings and check my work for some other study guide questions. I want to make sure I'm ready for my final. :) 3. The rectangular ...

Maths- Trigonometry

4. A,B and C are points on a horizontal plane. A is 75 m from C on a bearing of 210 degrees and the bearing of B from C is 120 degrees. The bearing of B from A is 075 degrees. From A the angle of elevation of the top T of a vertical towel at C is 42 degrees. Find a. the ...

trigonometry

From port Ilocandia to Camp Airstrip a plane flies on a course of 285deg. If Camp Airstrip is 1525 km further north than Port Ilocandia, find the distance from Port Ilocandia to Camp Airstrip.

trigonometry

calculate the linear velocity of an object rotating at an angular velocity "w" at distance "r" from the center . express the answer in centimeter per second. 1.r=10cm; w=20πrad/second 2.r=5cm; w=20πrad/second 3.r=12cm; w=25πrad/second 4.r=30cm; w=8πrad/second

Trigonometry - LONESTAR

Simplifying steps without using the calculator for: tan(cos^-1(-1/10)) cos(sin^−1(1/x)) Assume x is positive tan(cos^−1(12/13)) cos^−1(cos 150°) This is pretty much the entire section we are doing. My teacher is a robot and has us self teach ourselves. Can ...

Trigonometry

Let O be the origin and P be a point in the fourth quadrant on the x-y plane. Let 270<z<360 be the angle formed by OP with the positive x-axis. Similarly Q is a point in the fourth quadrant on the x-y plane where |OQ|=|OP| and the angle formed by OQ and the x-axis is 7z...

Trigonometry

A ship leaves port at 2:00 pm and sails in the direction S34 degrees W at a rate of 15mph. Another ship leaves port at 3:00 pm and sails in the direction S56 degrees E at a rate of 12mph. Find how far apart the ships are at 4:00 pm.

Trigonometry

Directions: Use a graphing utility to approximate the solutions of the equation in the interval [0,2π) by setting the equation equal to zero, graphing the new equation, and using the ZERO or ROOT feature to approximate the x-intercepts of the graph. (Note: These problems ...

Trigonometry law of cosine

A plane is flying with an airspeed of 200 miles per hour and heading 150°. The wind currents are running at 30 miles per hour at 175° clockwise from due north. Use vectors to find the true course and ground speed of the plane. (Round your answers to the nearest ten for the ...

Physics I for College

a rope that makes an angle of 30 degrees with the horizontal drags a crate along the floor. what must be the tension in the rope if a horizontal force of 40N is needed to drag the crate? please help me. i really didn't understand what my professor told me. he speak so fast. ...

Trigonometry Help please

1.If tan theta=3/4 and theta is an acute angle, find cos theta. 2.If sin theta=12/13 and theta is an acute angle, find cot theta.

Please Help!! Math

Solve for following applying spherical trigonometry... 1.Papua New Guinea (37° 45'N, 122°27'W)(since course was 260°) distance travelled =2250nm. A) use law of cosine to calculate a and thus altitude:or B) use law of sine to calculate N and thus longitude: or C) use law of ...

algebra

In a college, some courses contribute more towards an overall GPA than other courses. For example, a science class is worth 4 points; mathematics is worth 3 points; history is worth 2 points; and English is worth 3 points. The values of the grade letters are as follows, A= 4, ...

Trigonometry

Three oil platforms, Alpha, Beta and Gamma are situated in the North Sea.Beta is 12 km from Alpha and is on a bearing of 145 degrees from Alpha.Gamma is 16 km from Alpha and is on a bearing of 220 degrees from Alpha.Find the distance of Beta from Gamma. (Not sure how to ...

Trigonometry

I need help on both of these... Find the exact value of cotx if the terminal side of angle x contains the point (-5,-12). Find the exact value of secx for angle x that has a terminal side containing the point (-1,squareroot3)

algebra & trigonometry

The sum of three whole numbers is 7. The second number is 1 more than the twice of the third number. The sum of first and third number is 3 less than the second number. Find all the three numbers. Thanks

algebra & trigonometry

The sum of three whole numbers is 7. The second number is 1 more than the twice of the third number. The sum of first and third number is 3 less than the second number. Find all the three numbers. Thanks

Math

My problem involves right-triangle trigonometry. A man on a 135-ft vertical cliff looks down at an angle of 16 degrees and sees his friend. How far away is the man from his friend? How far is the friend from the base of the cliff? Does the 16 degrees go to the left of the ...

Trigonometry

Karla is riding vertically in a hot air balloon, directly over a point P on the ground. Karla spots a parked car on the ground at an angle of depression of 30o. The balloon rises 50 meters. Now the angle of depression to the car is 35°. How far is the car from point P?

Trigonometry

A plane at an altitude of 12,000 feet finds the angle of depression for a building ahead of the plane to be 10.4 degrees. With the building still straight ahead, two minutes later the angle of depression is 25.6 degrees. Find of the plane relative to the ground in feet per ...

Trigonometry

Verify/Solve the identities. 1.) SIN^1/2 X COS X-SIN^5/2 X COS X 2.) Long problem, but it's fun to solve! SEC^6 X(SEC X TAN X)-SEC^4 X(SEC X TAN X)

Trigonometry

Write an equation of the cosine function with the given amplitude, period, phase shift, and vertical shift. amplitude = 3, period = pi, phase shift = -3/4 pi, vertical shift = -3

Trigonometry

The diameter of the wheel is 165 feet, it rotates at 1.5 revolutions per minute, and the bottom of the wheel is 9 feet above the ground. Find an equation that gives a passenger's height above the ground at any time t during the ride. Assume the passenger starts the ride at the...

Trigonometry help

A boat drops an anchor to the bottom of a lake. The anchor rope makes a 15 degree angle with the boat. The anchor rope is 24 feet long. To the nearest foot how deep is the lake? Would I use the cos function giving me 23 or the sin function giving me 6 but how would my set up be?

Trigonometry

The angle elevation from a point A to the top of the Washington Monument is 32'. From point B, which is on the same line but 55 feet closer to the monument, the angle of elevation to the top is 38'. Find the length of the Washington Monument.

Trigonometry

A space shuttle pilot flying over the suez canal finds that the angle of depression to one end of the canal is 38.25 degrees and the angle of depression to the other end is 52.75 degrees. If the canal is 100.6 miles long, find the altitude of the space shuttle

Trigonometry- Help!

After one hour in flight, an airplane is located 200 miles north and 300 miles west of the airport. What is the magnitude of the plane's velocity? Round your answer to the nearest mile per hour. a) 22 miles per hour b) 128 miles per hour c )256 miles per hour d) 361 miles per ...

Trigonometry(please Clarify)

I posted before ; Write equivalent equations in the form of inverse functions for a.)x=y+cos theta b.)cosy=x^2 my answers were a.) x= y+ cos theta cos theta = x-y theta = cos^-1(x-y) b.) cosy=x^2 cos(y) = x^2 y = Cos^-1(x^2) your post confused me a little. Can you clarify if ...

trigonometry

a space shuttle pilot flying toward the suez canal finds that the angle of depression on one end of the canal is 38.5 degree and the angle of depression to the other end is 52.75 degree. if the canal is 100.6 mi long, find the altitude of the space shuttle.

Trigonometry

a person standing 400 feet from the base of a mountain measures the angle of elevation from the ground to the top of the mountain to be 25 degrees, the person then walk 500 feet straight back and measures the angle of elevation to now be 20 degrees, how tall is the mountain?

Trigonometry

Hello, I want to know what the amplitude and the phase shift would be for this question to model the equation Q. A pendulum is connected to a rope 3 m long, which is connected to a ceiling 4 m high. The angle between its widest swing and vertical hanging position is pi/3. If ...

Trigonometry

A hill in Colorado makes an angle of 15.0° with the horizontal and has a building at the top. At a point 75.0 feet down the hill from the base of the building, the angle of elevation to the top of the building is 55.0°. What is the height of the building? A. 84.0 feet B. 179...

MATH - GEOMETRY/TRIGONOMETRY

A 6 foot man stands by a 30 foot radio tower and casts a 10 foot shadow. How long is the shadow cast by the tower and what time is it? I got 50 feet for the length of the shadow. What I cannot find out is, what time is it? I NEED THE TIME OF DAY. **NOT** THE LENGTH OF THE ...

Algebra 2/ Trigonometry

The expression oos² θ/sin θ + sin θ is equivalent to 1) 1 + cos² θ 2) cos² θ 3) sin θ 4) csc θ

Trigonometry

The number of daylight hours in a day is harmonic. Suppose that in a particular location, the shortest day of the year has 7 hours of daylight and the longest day of the year has 18 hours. Then, we can model its motion with the function N=Asin(Bt) + C where t is expressed in ...

trigonometry

Verify that sec(θ)/csc(θ)-cot(θ) - sec(θ)/csc(θ)-cot(θ) = 2csc(θ) is an identity. can some help me through this? thank you!

algebra & trigonometry

A patient is not allowed to have more than 300 milligrams of cholesterol per day from a diet of eggs and meat. Each egg provides 150 milligrams of cholesterol. Each ounce of meat provides 100 milligrams of cholesterol. Write an inequality that describes the patient’s dietary...

trigonometry

1) show that: 1-cos2t divided by sin2t= TANt 2) show that: 1-(cos2t divided by (cos x cos)t)= (TAN x TAN)t

Math - Trigonometry

For how many values of theta such that 0<theta<360 do we have cos theta = 0.1? (Note that theta is a measure in radians, not degrees!) I'm kinda confused with the problem? Could someone help me? I'm thinking unit circle, so cos is the x coordinate. It would be easy if ...

Trigonometry

A wheel is rotating at 200 revolutions per minute .find the angular speed in radians per second. 200 rpm =200*2pi radians/1 minute (1 rotation = 2pi radians) = 400pi radians/60 seconds =20/3 radians/second You can follow the same procedure for the other two questions you asked.

Math

Bottom part of the greenhouse has a length of 350 cm, width of 220 cm, angle at the peak of the roof measures 90 degrees. Sketch the frame and label it with actual dimensions. Use trigonometry to find length of the roof pieces. Use a scale of 1:25 to calculate measurements for...

trigonometry

A box of 200kN is placed on a smooth inclined plane 28° with the horizontal. To prevent the box from sliding down the plane, a rope is tied to it and fastened to a peg on the top of the incline as shown. Determine the pull on the string assuming that the rope is held parallel...

trigonometry grade 11

Brit and Tara are standing 13.5 m apart on a dock when they observe a sailboat moving parallel to the dock. When the boat is equidistant between both girls, the angle of elevation to the top of its 8.0 m mast is for both observers. Describe how you would calculate the angle, ...

Trigonometry

The cast of Sesame Street decided to take a camping trip. being the rebels they are, elmo, cookie monster and oscar decided to camp alone. They each have their own tent and the tents are set up in a triangle. elmo and cookie monster are 10 meters apart. The angle formed at ...

Trigonometry

In the middle of town, State and Elm streets meet at an angle of 40º. A triangular pocket park between the streets stretches 100 yards along State Street and 53.2 yards along Elm Street. What formula for the area of the pocket park would you use?

Trigonometry

a satellite camera takes a rectangular-shaped picture. the smallest region that can be photographed is a 4km by 6km rectangle. as the camera zooms out, the length 1 and the width w of the rectangle increase at a rate of 3km/second. how long does it take for the area A to be at...

Trigonometry

a satellite camera takes a rectangular-shaped picture. the smallest region that can be photographed is a 4km by 6km rectangle. as the camera zooms out, the length 1 and the width w of the rectangle increase at a rate of 3km/second. how long does it take for the area A to be at...

Trigonometry

How do you simplify: (1/(sin^2x-cos^2x))-(2/cosx-sinx)? I tried factoring and creating a LCD of (sinx+cosx)(sinx cosx) (cosx-sinx), but cannot come up with the right answer. The answer is (1+2sinx+2cosx)/sin^2x+cos^2x,but I don't know how the book arrived at that answer. I'd ...

Trigonometry

Prove that 1/sin theta-tan theta and - 1/cos theta = 1/cos theta and + 1/sec theta+tan theta

Trigonometry

Each base angle of an isosceles triangle measures 42°. The base is 14.6 feet long. A) Find the length of a leg of the triangle. Round to the nearest tenth of a foot. B) Find the altitude of the triangle. Round to the nearest tenth of a foot.

Trigonometry

Each base angle of an isosceles triangle measures 42°. The base is 14.6 feet long. A) Find the length of a leg of the triangle. Round to the nearest tenth of a foot.  B) Find the altitude of the triangle. Round to the nearest tenth of a foot.

trigonometry

Solution of problem:from the top of a building 55 ft high, the angle of elevation of the top of a vertical pole is 12 degrees, At the bottom of the building, the angle of elevation of the top of the pole is 24 degrees. find the height of the pole.

Math

Trigonometry Problem: The good ship Bravery is 30 km due west of the good ship Courageous. The Bravery sets out on a bearing of 030° at a speed of 20km/hr. The Courageous sets out on a bearing of 345° at a speed of 25km/hr. Will the ships collide?

trigonometry

A wheel with a 20-inch radius is marked at two points on the rim. The distance between the marks along the wheel is found to be 3 inches. What is the angle (to the nearest tenth of a degree) between the radii to the two marks? someone helped me on this before: angle/360=3/(...

Trigonometry

A cat, sitting on top of a tree, spots a dog and a firefighter, both on flat ground below. From the cat's point of view, the dog is 10m south, at an angle of depression of 65 degrees, and the firefighter is some distance east of the tree, at an angle of depression of 50 ...

trigonometry

a restaurant uses a cable for the servers to slide orders down to the kitchen. the end where the servers place the order is 5 feet high. the end where the kitchen receives the order is 1 foot high. the angle of elevation from the kitchen to the servers stand is 25 degrees. ...

Precalculus with Trigonometry

Calculate the work done by gravity as a 10 kg object is moved from point A = (0,0,0) to point B = (1,2,0). We are given s = (x sub f - x sub I)x(hat) + (y sub f - y sub I)y(hat) + (z sub f - z sub I)z(hat). Sorry if that doesn't make sense. I think I have to plug in the ...

Trigonometry

Please show me the work so i understand 2. Find the reference angle of -11π/3. 5. If θ = –18°, find the exact value of θ in radians. 6.If θ = 3, find the value of θ in degrees correct to the nearest tenth of a degree. 13.The radius of a circle ...

Advanced Functions/Precalculus

Trigonometry Questions 1. Using a compound angle formula, demonstrate that sin2π/3 is equivalent to sin π/3 2. The expression sinπ is equal to zero, while the expression 1/cscπ is undefined. Why is the identity sin(theta)=1/csc(theta) still an identity? 3. ...

math- Trigonometry

If cos degree equals to 0.8641  What is Sin degree?  I have no idea how to find this.  Please help me. I got help from two people, but I'm not getting the answer and how they got the numbers either. Someone says: cos^2+sin^2=1  sinDegree=sqrt(1-cos^2degree) Another person ...

trigonometry

How do you work these out? sec u- 1 / 1-cos u = sec u sec x-cos x= sin x tan x 1/sin x - 1/csc x= csc x - sin x

Trigonometry

in triangle abc, if sin c= (sin a + sin b )/ ( cos a + cos b ) prove that triangle abc is a right-angle triangle.

Trigonometry

if cos x=2/3 and x is in quadrant 4 find tan(x/2),sin(x/2),and cos(x/2) i got sin(x/2)=squr 1/6 tan(x/2)=squr 2/6 cos(x/2)=squr 5/6

Trigonometry

John stands on top of a little lighthouse looking out at a nearby tall lighthouse that is 200 feet away. He looks at the top of the tall lighthouse with a 3 degree angle of elevation, but looks at the bottom of the tall lighthouse with 6 degree angle of depression. Find the ...

Trigonometry

a. Write a formula for Q as a function of t. b. What is the value of Q when t=10 1. Initial amount 2000; increasing by 5% per year 2. Initial amount 112.8; decreasing by 23.4% per year 3. Initial amount 5; increasing by 100% per year

trigonometry ASAP!

wendell is setting concrete on a triangular patio. one side of the patio is 12.9 feet and another side is 15.2 feet. the angle opposite the 15.2 foot side is 68 degrees. one bag of concrete covers an area of 5 square feet. how many bags of concrete will wendell need to cover ...

Trigonometry

A building 200 feet tall casts an 80 ft long shadow. If a person looks down from the top of the building which of the following is the measure of the angle between the end of the shadow and the vertical side of the building to the nearest degree? I understand that you would ...

Trigonometry

From the top of a building 85ft high, the angle of elevation of the top of a vertical pole is 11 degree 6'. At the bottom of the building the angle of elevation of the top of the pole is 26 degree 7'. Find the height of the pole and the distance of the pole from the following.

Trigonometry - Identities

If tan 2x = - 24/7, where 90 degrees < x < 180 degrees, then find the value of sin x+ cos x. I applied various identities and tried manipulating the problem to get sin x + cos x = sin(arctan(-24/7)/2) + cos(arctan(-24/7)/2) I also played around with the half-angle ...

Math, Trigonometry

daylight in Calgary, AB each month is show in the table below.? Month Daylight (hrs) Jan 8.50 Feb 10.03 March 11.91 April 13.87 May 15.57 June 16.48 July 16.03 Aug 14.51 Sept 12.63 Oct 10.68 Nov 9.20 Dec 7.99 a) Determine the regression equation that models the number of ...

Trigonometry

A point on the rim of a wheel of unknown radius in a pulley system has a velocity of 16 in/min. The wheel is making 4 rpm. If the radius of the other wheel is 8 inches, find the 8" wheel's rpms and the unknown wheel's radius. I got a radius of about 0.637" for the unknown ...

trigonometry

please help two boundary lines of a piece of property intersect at an angle 85 deg.. it is desired to cut off a triangular portion of the property which will be one acre (43560 sq. ft.) in area by means of a straight fence. If the fence begins at a point on one boundary 250 ft...

trigonometry

show that : sin(A+B).sin(A-B)=Cos^2B - Cos^2A =sin^2A - sin^2B

Math - Trigonometry

Let f(x) be a polynomial such that f(cos theta) = cos(4 theta) for all \theta. Find f(x). (This is essentially the same as finding cos(4 theta) in terms of cos theta; we structure the problem this way so that you can answer as a polynomial. Be sure to write your polynomial ...

Trigonometry

I need help: If vector u has a magnitude of 4 meters and a direction of 17 degrees and vector v has a magnitude of 6 meters and a direction of 133 degrees. Find the magnitude of the resultant vector of u + 3v.

Trigonometry

while standing at the left corner of the schoolyard in front of her school, Suzie estimates that the front face is 8.9m wide and 4.7m high. from her position, Suzie is 12m from the base of the right exterior wall. she determines that the left and right exterior walls appearto ...

Math (trigonometry)

From a boat on the water, the angle of elevation of the drop of a cliff is 31°. From a point 300 m closer, the angle of elevation is 33°. Find the height of the cliff. the answer should be 2411 m. I had tan31° = h/x+(x-300) tan33° = h/x-300 -> (x-300)tan33° = h. I ...

Trigonometry

Verify the identities. 1.) SIN[(π/2)-X]/COS[(π/2)-X]=COT X 2.) SEC(-X)/CSC(-X)= -TAN X 3.) (1 + SIN Y)[1 + SIN(-Y)]= COS²Y 4.) 1 + CSC(-θ)/COS(-θ) + COT(-θ)= SEC θ (Note: Just relax through verifying/solving these nice fun looking math problems! ...

Trigonometry

The angle elevation from a point A to the top of the Washington Monument is 32 degrees. From point B, which is not the same line but 55 feet closer to the monument, the angle elevation to the top is 38 degrees. Find the height of the Washington Monument.

trigonometry

from a point A on the side of straight road, the angle of elevation of the top of the electric pole is 15°20'. from a point B on the same side of the road, the angle of elevation of the top of the pole is 10°52'. If the distance of A and B is 50 meters, what is the height of...

Trigonometry

A plane leaves airport A and travels 560 miles to airport B at a bearing of N32E. The plane leaves airport B and travels to airport C 320 miles away at a bearing of S72E. Find the distance from airport A to airport C.

Trigonometry

Find cotangent theta given that cosecant theta equals -3.5891420 and theta is in the third quadrant. I was using the trig identity 1+cot^2theta=csc^2theta I wanted to isolate cotangent so I plugged in 1/sin (-3.5891420) and then squared my answer. I then subtracted one from ...

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