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 Sujet: cosine
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98 articles trouvés pour ce sujet.

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 probleme sin cos 2006-02-19 Thibault pose la question :mon probleme commence par: f(x)=sinx (sinx+1)+ cos²x donc en le dévellopant on trouve: f(x)= sin²x + sinx + cos²x et apres ce que je ne comprend pas est que par la suite on trouve: f(x)= 1+sinx qu'est-ce qui fait que l'on trouve ce resultat??Claude Tardif lui répond. 0.366 x cos square (02 degree 17 mins 27 seconds) 2018-03-12 michael pose la question :what is 0.366 x cos square (02 degree 17 mins 27 seconds) what is 0.366 x cos square (88 degree 26 mins 45 seconds)Penny Nom lui répond. A footballer angle 2018-02-14 Kim pose la question :Two goal posts are 8m apart. A footballer is 34m from one post and 38m from the other. Within what angle must he kick the ball if he is to score a goal.Penny Nom lui répond. Solve the equation completely cos 2x = 1 2017-06-08 Lava pose la question :Solve the equation completely cos 2x = 1Penny Nom lui répond. How far apart are the boats? 2016-12-13 Halley pose la question :Two boats leave port at the same time. Boat A travels east at a speed of 12 km/hr. Boat B travels southwest at a speed of 14 km/hr. After two hours, how far apart are the boats? North is 0 degrees. How do I figure this out. ThanksPenny Nom lui répond. Two airplanes 2015-04-14 john pose la question :two planes leave an airport at the same time, one going northwest (N35*W)at 400 mph and the other going east at 332 mph. How far apart are the planes after 4 hours to the nearest mile?Penny Nom lui répond. Trig functions and the unit circle 2014-10-02 Jake pose la question :I was wondering what conclusions can be drawn about the trigonometric functions and how they work about the circle. Can you also please give me an explanation for it? Thank you.Penny Nom lui répond. A triangular chicken pen 2014-04-27 Cierra pose la question :Margaret has two lengths of fence, 20 meters and 24 meters, for two sides of a triangular chicken pen. The third side will be on the north side of the barn. One fence length makes a 75° angle with the barn. How many different pens can she build if one fence is attached at the corner of the barn? What are all the possible lengths for the barn side of the pen? Not sure what they are asking here... please show step by step what to do! Thank you so much!Penny Nom lui répond. The sides of a triangle 2014-04-06 Michael pose la question :I am supposed to sove for the length of side "b" of an irregular triangle. I am given the following: Side a: 65' Side b: Find this length Side c: 50' Angle A: unknown Angle B: unknown Angle C: 52 degrees I am supposed to use the law of cosines to solve for side "b" and my teacher says there is no mistake in the "givens" for the problem. I do not see how this can be done using the law of cosines and i have not figured out how to sove for angle B to use the law of cosines.Penny Nom lui répond. A triangle problem 2013-10-02 raneem pose la question :ABC is a triangle in which : BC=20cm. M(infinity cos x 2006-12-07 Katie pose la question :I was wondering if it was possible to find: lim x-->infinity cos x Stephen La Rocque lui répond. cos2x=1 2006-11-21 Christina pose la question :I'm have a hard time solving cos2x=1 for exact values between 0<_x <360Stephen La Rocque and Penny Nom lui répond. A trig problem 2006-06-24 Greg pose la question :A and B are two towers, B being 4 km due east of A. The true bearings of a flagpole, C, from A and B are α east of north and α west of north respectively. The true bearings of a second flagpole, D, from A and B are (α + β) east of north and (α - β) west of north respectively. Assuming A, B, C, and D are on level ground, and that α = 25, β = 10, find the distance between C and D.Penny Nom lui répond. The chord length of a polygon 2006-06-14 Krishna pose la question :I have to find out the chord length of a polygon - Tetradecagon ! The Radius of the Circle is 11.5 Cms. The Circle is intersepted by 14 arcs. Then how to find out the chord length?Stephen La Rocque lui répond. The interior angles of a right triangle 2006-05-20 Greg pose la question :I am wondering if there is a way to figure out the interior angles of a right triangle if we know ONLY the side lengths, and the trick is, we CANNOT use arctangent!Leeanne Boehm and Penny Nom lui répond. Solve the equation cos x = sin 20 where x is acute. 2006-03-26 Elle pose la question :Solve the equation cos x = sin 20 where x is acute.Stephen La Rocque lui répond. Three towns are located at the vertices of an equilateral triangle 2006-03-20 A student pose la question :three towns are located at the vertices of an equilateral triangle. The towns are 8, 5, and 3 miles, respectively, from a store. How far apart are the towns?Chris Fisher lui répond. How do you find the angles in a triangle? 2006-01-27 Keith pose la question :How do you find the angles in a triangle if you know the lengths of the sides?Chris Fisher and Penny Nom lui répond. The period of sin(x) + cos(x) 2005-07-21 A student pose la question :WHAT IS THE PERIOD OF SIN(X)+COS(X)?Penny Nom lui répond. The tide at a boat dock 2005-01-11 Abraham pose la question :The tide at a boat dock can be modeled by the equation y = -2cos(pi/6 t) + 8, where t is the number of hours past noon and y is the height of the tide, in feet. For how many hours between t=0 and t=12 is the tide at least 7 feet?Penny Nom lui répond. Modelling monthly temperature with a cosine 2004-12-25 Regis pose la question :The average monthly temperature for a location in Ontario as a function of month number can be modelled using the equation y = a cos[k(t + b)] + d.Harley Weston lui répond. Solving triangles 2004-10-30 Allen pose la question :Solve the following triangles. Given 1. B = 20 Degrees, a = 25, b = 16 2. A = 35 Degrees, b = 2, c = 3 3. A = 32 Degrees, C = 44, c = 20Harley Weston lui répond. Finding bearings 2004-05-24 James pose la question :This question is about finding bearings. A boat race starts from point A, goes North to Point B, a distance of 1000 meters. The course is triangular. The bearing from point B to point C is South 70degrees West. The distance from Point B to point C is 1500 meters. Find the course bearing from C to A. Penny Nom lui répond. Cosine of 35 degrees 2004-03-03 Jason pose la question :How do you find the exact solution to cosine 35 degrees.Chris Fisher lui répond. Sin(3x), cos(3x) and tan(3x) 2004-01-28 Jon pose la question :What is the identity for cos3x, sin3x, and tan3x? In class, we learned double angel identities and were asked to find out the identity to these three trig functions. If you can help, please do. Also, i know that the cos4x- sin4x is the same as cos2x. Is cos8x-sin8x = cos2x also true? Thank you.sChris Fisher lui répond. Laws of sines and cosines 2003-11-23 A parent pose la question :On the one side of a stream lines PA= 586.3 feet, PB = 751.6 feet are measures, angle APB being 167 degrees and 36 min. Q is a point on the opposite side of the stream. Angle PAQ=63 degress and 18 min and PBQ=49 degrees and 24 min. Find PQ.Penny Nom lui répond. Odd powers of sine and cosine 2003-06-25 Antonio pose la question :Can you please tell me how to integrate a trig function involving sine and cosine? I know if the powers of both the sine and cosine are even and nonnegative, then I can make repeated use of the power-reducing formulas. But for the question I have on my hand, the powers of both sine and cosine are odd: ( sin3x + cos7x ) dx. Harley Weston lui répond. Two trig problems 2003-06-10 Bett pose la question :I have this ongoing trouble with trig and solving triangles with laws of cosines and sines!! For example if it asks to solve triangle FGH, given angle G=102.7 , side f=14.2, and h=18.6. Now do I use law of cosines because I don't have the measure of an angle and length of the opposite side??I don't know where to go from here,I am totally confused!!! I also have a problem with this word problem I have been doing. It asks: An airplane flies 847.5 km at a bearing of 237.3 degrees. How far south and west fo its original position is it? Huh? Please help! Penny Nom lui répond. sin theta = 7/8 2003-05-07 Patty pose la question :If sin0 = 7/8 and 0 is in quadrant 2, find the other five trigonometric functions of 0. (report your answers in radical form)Penny Nom lui répond. Write sin(3x) in terms of sin(x) 2003-05-05 A student pose la question :Write sin 2x in terms of sin xPenny Nom lui répond. How far apart are the transmitters? 2002-05-18 Jeff pose la question :A ship at sea is 70 miles from one transmitter and 130 miles from another. The measurement of the angle between the signals is 130 degrees. How far apart are the transmitters?Penny Nom lui répond. The law of cosines and obtuse angles 2002-05-09 Bryant pose la question :The question that I am pondering is that I need to derive the law of cosines for a case in which angle C is an obtuse angle.Penny Nom lui répond. A trigonometric identity 2002-03-22 Debby pose la question :I am stuck on a problem and wondering if you can help?? It is: Prove the following: sec2(X)+csc2(X) = sec2(X)csc2(X)Harley Weston lui répond. sin 2x = cos 3x 2002-02-25 Allan pose la question :solve: sin 2x = cos 3x Primary question: how do you handle the cos 3x? Paul Betts and Chris Fisher lui répond. Adding vectors 2002-01-12 Lena pose la question :how do you add vectors together? If you are given the length and angles of both vectors and are asked to add/subtract them, how do you do it? I know you are supposed to do the head to tail method, but whenever i try it i get the wrong answer. I need help setting it up. example: A is 2.7cm, and 60 degrees, B is 1.6cm and 135 degrees, find the magnitude and amplitude Penny Nom lui répond. The tangent function 2002-01-12 Justine pose la question :if you know that sin45degress = cos45degrees, how do you know that tan45degrees = 1?Penny Nom lui répond. A trig identity 2001-07-27 Jeff pose la question :prove this identity and show steps tan(x/2+pi/4)=secx+tanxHarley Weston lui répond. The speed of the boat 2001-07-12 Sharon pose la question : A motor boat is travelling in a southeasterly direction in water that is flowing from the south at 2km per hour. Show that the speed of the boat is (6 times the square root of 2) km per hour, given that it can travel at 10km per hour in still water.Penny Nom lui répond. The angles in a triangle 2001-05-11 Nikki pose la question :Find the measure, to the nearest degree, of each angle of a triangle with sides of the given lengths. 26, 35, 40 Penny Nom lui répond. The unit circle and trigonometry 2001-04-05 Ashley pose la question :"My teacher wants us to find out what a unit circle is, which I found out, a circle with the radius of 1, but the problem is he wants us to show the relationship between the unit circle and the sine(30,45,60 degrees), cosine(30,45,60 degrees),and tangent ratios(30,45,60 degrees). I need help with this and my teacher will not help us out. Thanks very much ...Penny Nom lui répond. The law of cosines in the real world 2001-02-21 Hope pose la question :Do you have any examles and/or labs that show how the law of cosines is used in the real world?Harley Weston lui répond. Law of cosines 2001-02-20 Emily pose la question :I missed a few days of class and I can't figure out how to solve Law of Cosines problems. I have the notes and formulas but I can't figure out how to do the math involved to answer the problems. I am also getting confused about how to use degrees and seconds in the Law of Sine and Cosine. I can't seem to get the correct answers and I don't really know how to solve them and enter them into my TI 86.Harley Weston lui répond. The laws of sines and cosines 2001-01-02 Faydene pose la question :Can the sine /cosine rule be applied to a right -angle triangle to find a particular solution or are these 'rules' applied only when the triangle is not right angled?Penny Nom lui répond. Trig identity crisis 2000-11-29 Rhiannon pose la question :I have tried many times to find the answer to these problems but I can't I am in grade 12 tan(x)=csc2(x)-cot2(x) cos(x)/csc(x)-2sin(x)=tan(x)/1-tan(x) cos(x)[ tan2(x)1-1]/cos2(x)+sin2(x)=sec(x) Harley Weston lui répond. Some trigonometry 2000-08-11 Angela pose la question :I have some PreCal questions. I am a student at the secondary level. I would be very grateful for your help. Solve the equation for theta (0 <= theta < 2pi). tan2(theta) = 3 I know sec2(theta) -1 = tan2(theta) ...Harley Weston lui répond. Using the inverse sine function 2000-05-31 Nelson Rothermel pose la question :This has me completely baffled. I have to use the laws of sine or cosine to find the angles of a triangle when I have 3 sides, so I can't go 180-x-y when I have 2 angles. Now, I have a triangle with values of 3, 7, and 9. Here are the steps I used (A,B,C are angles; a,b,c are opposite sides): angle A (16.1951 degrees): cos-1*((b2+c2-a2)/(2*b*c)) angle B (40.6011 degrees): sin-1*(b*sin(A)/a) angle C (56.7962 degrees): sin-1*(c*sin(A)/a) If you notice, A+B+C does not equal 180. According to the book, A and B are correct, but C is supposed to be 123.2038 degrees. Why doesn't it work??? Harley Weston lui répond. Solve 2sin 3x-1=0 2000-05-11 Cynthia pose la question :How would you solve 2sin 3x-1=0? I don't know what to do with the 3.Penny Nom lui répond. sin(7pi/12) 2000-05-04 Kristel pose la question :What is the exact value of sin 7pi/12?Chris Fisher and Paul Betts lui répond. Triple angle formula 2000-02-23 Sara pose la question :Can one derive a triple angle formula for sine and cosine? If so, how? Chris Fisher lui répond. A trig identity 2000-02-17 Eric pose la question : Question: How do I solve this problem? ` sin3x cos3x _____ - _____ = 2 sinx cosx `Chris Fisher lui répond. Sines & cosine laws 1999-12-10 Pierre Boivin pose la question :Triangle LMN, angle L=71 degree , LM= 7.2 , MN=8.3 , ln= 5.9 The questiion was to find angle M. Using the cosine law I found the answer to be 44 degree. It is also the book answer. Using the sines law I found the answer to be 42.2 degree. why can't I use the sines law.Chris Fisher lui répond. Cos x = -1/2 1999-12-01 Pierre Boivin pose la question :When I factor[ 2cos (square) - 5cos -3], I get (2cos + 1)(cos - 3). 2cos + 1 = 0, 2cos = -1, cos = -0.5,. Using inv cos on calculator, I get 120 degree related angle. When I graph I get two values, between 90 and 180 degree and between 180 and 270 degrees. How do I find those two values. How do use 120 degree in relation with the x axis.Penny Nom lui répond. A Trigonometry Question 1999-08-28 Diane Simms pose la question :My question is can the following be factored. I am a teacher who needs the factors to this right away. 2 Sin2X + 2 SinX CosX - 1= 0 Harley Weston lui répond. From an airport control tower 1999-08-04 Pammy pose la question :Hi I am a 30 yo mature age student doing my HSC but am having difficulty understanding this, if you can help me. From an airport control tower, a Cessna bears 023 degrees T and is 27km away. At the same time, a Boeing 767 bears 051 degrees T and is 61km from the tower. Both planes are at the same height. i) What is the size of angle ATB? ii) Using the cosine rule to calculate the distance the planes are apart, to nearest kilometre. I figured out and drew the triangular diagram but can't figure out the rest and which formula to use. sorry about this, thankyou kindlyHarley Weston lui répond. Sin 4A 1999-06-22 Ryan Cochrane pose la question :If sinA = 4/5, and A is a first quadrant angle, find sin4AHarley Weston lui répond. Cos(x) Cos(2x) Cos(4x)=1/8 1997-09-24 Tan Wang pose la question :How many distinct acute angles x are there for which cosx cos2x cos4x=1/8? Chris Fisher Harley Weston and Haragauri Gupta lui répond. Finding the Mine 1997-06-23 Billy Law pose la question :Tom is gold prospector. On his last trip out from town, he headed 35 degree South of West to a lake where he had lunch. The lake was 24 km out of Town. He then headed due East for 35 km before Doubling back on bearing of 15 degree South of west for 20 km to reach his mine. By converting to Cartesian coordinate before doing vector additions do the following: a) Calculate the position of the mine from town in term of a distance and a direction. ...Harley Weston lui répond. A problem with arccos. 1997-06-09 Vanessa Chan pose la question :Prove: arc cos4/5 + arc cos (-5/13) = arc cos (-56/65) Harley Weston lui répond. Ajax, Beverley, Canton and Dilltown 1997-03-14 S. Johnson pose la question :The following towns are placed on a coordinate system. Ajax at (-x,z), Dilltown at (-10,0), Canton at (0,0) and Beverly at (0,10). The roads from Beverly to Canton and from Canton to Dilltown are perpendiculat to each other and are each 10 miles in length. A car traveling at all times at a constant rate, would take 30 minutes to travel straight from Ajax to Canton, 35 minutes to travel from Ajax to Canton via Beverly, and 40 minutes to travel from Ajax to Canton via Dilltown. What is the constant rate of the car, to the nearest tenth of a mile per hour.Chris Fisher and Harley Weston lui répond. A trig problem 1996-12-13 S. Johnson pose la question :sin t + cos t = 1/5. Find ALL exact values of cot t, given the original equation.Harley Weston lui répond. Height of a Hotel 1996-11-07 Irene pose la question :"Irene" is to determine the # of floors in a hotel 500 feet up the street. Irene is on the 10th floor of an office building and can measure the angle of elevation to the top of the hotel, 57 degrees. Her view of the entire building is obstructed. If the street rises at an angle of 8 degrees from the office building to the hotel and the average distance between floors is 11 feet, how many floors are on the hotel?Penny Nom lui répond. A trig identity 1996-03-11 Azmat Hussain pose la question :Is there an easier/another way to prove the trig identity cos(a+b) = cos(a)cos(b)-sin(a)sin(b)?Penny Nom lui répond.

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