# If cos(t)=(-7/8) where pi

4,795 questions, page 33
1. ## math (trig)

For the following value of cos 0, determine the rad value of 0 for pi < 0 < 2pi (greater than or equal to pi and 2pi) -1/2 I don't understand I found out that the inner circle val is pi over 3. But I can't work out how to find 0

asked by Laura on January 28, 2018
2. ## Trig

How do I prove the following Identity? sec x(sec x-cos x)=tan^2x If there is a certain website or suggestion to help with these type of equations I would greatly appreciate it. I've been studying these for a while but still get pretty confused.

asked by Mel on May 31, 2011
3. ## Math trigonometry

A cos wave has its first maximum at the point (pie/2, 2) and its first minimum at (5pie/2, -4) what is the equation of the function? I remember writing 3cos(1/2(x-pie/2)-1 but I'm sure that it's wrong ?

asked by Kim on December 7, 2015
4. ## Trigonometry

I need help proving the following identity: 4(sin^6(x)+cos^6(x)) = 4-3sin^2(2x) I am completely lost, if anybody can please give me a step-by-step guide to figuring this out, I would be forever grateful!!

asked by Rick on June 26, 2011
5. ## Math trig

Hello guys. I am just wondering if tan^2 A (tan squared A) = sin^2 A /cos^2A And 2tan A = 2sin A / 2cos A This has been bothering me when I have to simplify trig. Thanks in advance.

asked by Jack on June 1, 2016
6. ## Calculus (polar coordinates)

Use polar coordinates to set up the double integral x dA, where the bounds are given by the region lying in the intersection of the 2 circles r = 2 sin (theta) and r = 2 cos theta. Thanks for any help!

asked by Lucie on February 6, 2016
7. ## PRE-CAL

Factor the trigonometric expression. There is more than one correct form of the answer. cot^2 x + csc x − 19 NOT SURE WHETHER TO REPLACE THE COT WITH COS^2X/SIN^2X THEN CSCX TO 1/SINX?

asked by RACHEL on October 17, 2016
8. ## Math

What is the exact answer to cos^2x - sin^2x = 0 for between 0 and 2pi? I got x = pi/4 and x = 5pi/4. But the answer key says there are two additional answers which are 3pi/4 and 7pi/4. I don't know how to get these. Any help is much appreciated!

asked by Ann on May 10, 2013
9. ## calculus

At what points does the helix r = sin(t), cos(t), t intersect the sphere x 2 + y 2 + z 2 = 37? (Round your answers to three decimal places. Enter your answers from smallest to largest z-value.)

asked by Anonymous on September 26, 2010
10. ## 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
11. ## Physics

A box of textbooks of mass 25.3 kg rests on a loading ramp that makes an angle (ALFA) with the horizontal. The coefficient of kinetic friction is 0.260 and the coefficient of static friction is 0.330 . A) As the angle (ALFA) is increased, find the minimum

asked by Jasijo on November 18, 2006
12. ## math

Short Answer: Type your answer below each question. Show your work. 1 Verify the identity. Show your work. cot θ ∙ sec θ = csc θ 2 A gas company has the following rate schedule for natural gas usage in single-family residences:

asked by nax on September 28, 2018
13. ## math

Short Answer: Type your answer below each question. Show your work. 1 Verify the identity. Show your work. cot θ ∙ sec θ = csc θ 2 A gas company has the following rate schedule for natural gas usage in single-family residences:

asked by nax on September 28, 2018
14. ## trignometry

In the right triangle shown below, the length of AB is 8 units, ¡ÏA measures 60¡ã, sin 60¡ã ¡Ö 0.866, cos 60¡ã ¡Ö 0.5, and tan 60¡ã ¡Ö 1.73. Approximately how many units long is BC , to the nearest hundredth of a unit? A. 4.00

asked by gt on April 24, 2013
15. ## URGENTANIUS!!

If the given point is on the terminal arm of an angle A in stadard position. 0 degrees more than or equal too A and less than or equal too 180 degree, find sin A and cos A: a) (6,8) b) (-5,12) Can you tell me how you get it because I do not understand it

16. ## MATH help

sketch + describe graph of the curve parametrized by: x=1-3cos^(2)t y=-2+4sin^(2)t -infinity less than t less than infinity how would i go about solving this. i know that usually i can solve for t and than plug that in. But for this, i tried using cos^2 +

asked by Amy on September 5, 2011
17. ## Math

Find the components of the unit vector that makes an angle of 210 degrees counterclockwise with the positive x-axis (-√3/2,-1/2) which would be the same as (cos 210º,sin 210º)

asked by Alejandro on April 16, 2007
18. ## Calc

sinx+x^2y=1 use implicit differentiation to find the second derivative. For the first derivative I got (cos(x)+2xy)/x^2. I have a feeling that is wrong, can someone please help and show steps on how to do this problem. (studying for a midterm).

asked by Anonymous on June 8, 2016
19. ## Precalculus

The graph of 4/(2-cos(theta)) forms a closed curve. The area of the region inside the curve can be expressed in the form k \pi. What is k^2? So I tried this problem and I got it to be an ellipse 1 = (((x + 8/6)^2)/((16/3)^2)) + ((y^2)/4)) Is this correct?

20. ## trig

Consider the angle in standard position whose measure is radians. The terminal side of this angle is in the third quadrant and lies on the line given by y=10x. Find sin and cos.

asked by yo on October 10, 2011
21. ## Math (Trig) a.s.a.p, thanks!

verify the identities: 1.) 2tanx-(1+tanx)^2 = -secx 2.) cos(x-330degrees)=1/2(ã3cosx-sinx) *the ãis only over the 3* 3.) 1+cos2x/sinx=cotx any help is greatly appreciated!!

asked by Hailey on April 10, 2008
22. ## 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
23. ## trigonometry

im really stuck on these, can anyone help me and also explain how to solve them: Find the exact values of s in the given intervals that have the given circular function values. 1. [pi/2, pi]; sin s=sqrt2/2 2. [pi/2, pi]; cos s=-sqrt3/2 thnks:)

asked by y912f on January 15, 2009
24. ## trig

Determine if the value of each trig function is positive, negative, zero, or undefined. a) tan 310 degrees b) cos 7pi/6 c) sin -245 degrees d) sec( -7/2)

asked by Anonymous on January 26, 2012
25. ## physics

a body oscillates with simple harmonic motion along the x axis. Its displacement varies with time according to the equation x = 5.0 cos (pt). The magnitude of the acceleration (in m/s2) of the body at t = 1.0 s is approximately a. 3.5 b.14 c.43 d.4.3

asked by eugene on April 11, 2011
26. ## physics

In an engine, a piston oscillates with simple harmonic motion so that its position varies according to the expression x = 4.7 cos ( 4t + π/6 ) where x is in centimeters and t is in seconds. Find the period of the motion.

asked by juan on February 28, 2016

If the given point is on the terminal arm of an angle A in stadard position. 0 degrees more than or equal too A and less than or equal too 180 degree, find sin A and cos A: a) (6,8) b) (-5,12) Can you tell me how you get it because I do not understand it

asked by Priya on December 18, 2012
28. ## PASCUAL DE ANDAGOYA

SE EL MOVIMIENTO DISTACIA Y CENTIMETRO Y TIEMPO EN S X =3 COS 5+ ENCUENTRE LA AMPLITUD, LA FRECUENCIA ANGULAR EL PERIODO, LA FRECUENCIA LA VEL MAXIMA LA ACERERACIO9N MAX

asked by YEISON on September 10, 2009
29. ## trignometry

In the right triangle shown below, the length of AB is 8 units, ¡ÏA measures 60¡ã, sin 60¡ã ¡Ö 0.866, cos 60¡ã ¡Ö 0.5, and tan 60¡ã ¡Ö 1.73. Approximately how many units long is BC , to the nearest hundredth of a unit? A. 4.00

asked by gt on April 24, 2013
30. ## PASCUAL DE ANDAGOYA

SE EL MOVIMIENTO DISTACIA Y CENTIMETRO Y TIEMPO EN S X =3 COS 5+ ENCUENTRE LA AMPLITUD, LA FRECUENCIA ANGULAR EL PERIODO, LA FRECUENCIA LA VEL MAXIMA LA ACERERACIO9N MAX

asked by YEISON on September 10, 2009
31. ## Math

Hi! My teacher told my class that the answer to this question is "1-sin x/cosx" but she wants us to figure out why. I tried solving it but I didn't end up with the answer given. Can someone help me? Thank you! Problem: cos x/1+sinx

asked by Kelly on February 8, 2015
32. ## math

If cotalpha = root 3, calculate (sin alpha)*(cot alpha) - cos^2alpha exactly. can you plzzz help urgent because I have a major test tommorow thnx for all your help

asked by Gagan on April 29, 2009
33. ## Calculus 1

Sketch the graph of f by hand and use your sketch to find the absolute and local maximum and minimum values of f. (If an answer does not exist, enter DNE.) f(t) = 6 cos t, −3π/2 ≤ t ≤ 3π/2

asked by TayB on October 20, 2015
34. ## computer programming

Make an Maplet that does the simple calculator funtions as addition, subtraction, multiplication, division, factorial, sin(), cos(), tan(). (using maplet in maplesoft)

asked by david on April 22, 2012
35. ## maths...

Differentiate ln [x+√(x^2+1)] with respect to x hence evaluate limit 0 to 1 ∫ 1/√(x^2+1) dx _________________________________________ Use the identity cos3x=4cos^3x-3cosx, find ∫cos^3x dx * Is there a printing error in the question? the limit is

asked by Aoi on June 19, 2009
36. ## trig (pre-cal class)

Suppose è is an acute angle of a right triangle. For this function, find the values of the remaining five trigonometric functions of è. Round to four decimal places. sin è = 0.1 cos è = tan è = cot è = csc è = sec è =

asked by Allison on December 15, 2011
37. ## Pre-Cal

Suppose è is an acute angle of a right triangle. For this function, find the values of the remaining five trigonometric functions of è. Round to four decimal places. sin è = 0.1 cos è = tan è = cot è = csc è = sec è =

asked by Kelley on December 15, 2011
38. ## Chemistry

Which of the following molecules is/are bent or V-shaped? C2H2 SiF4 H2S SO2 CF4 HCN NH3 COS H2O O3 SO3 AsH3 CS2 BF3 N2O HN3 PF3

asked by Anonymous on April 5, 2016
39. ## Chemistry

2. Which of the following molecules is/are trigonal pyramidal? N2O NH3 C2H2 SiF4 HN3 HCN SO3 H2S CF4 PF3 H2O BF3 COS O3 SO2 CS2 AsH3

asked by S on December 7, 2015
40. ## Physics

Interactive LearningWare 22.2 at wiley/college/cutnell reviews the fundamental approach in problems such as this. A constant magnetic field passes through a single rectangular loop whose dimensions are 0.35 m 0.55 m. The magnetic field has a magnitude of

asked by Mary on October 5, 2007
41. ## Calculus (Area Between Curves)

Find the area of the region IN THE FIRST QUADRANT (upper right quadrant) bounded by the curves y=sin(x)cos(x)^2, y=2xcos(x^2) and y=4-4x. You get: a.)1.8467 b.) 0.16165 c.) 0.36974 d.) 1.7281 e.) 0.37859

asked by Mishaka on February 29, 2012
42. ## physics

find by calculation,the resultant two equal forces of 6N each acting at a 4N point at an angle of (a) 60 degree (b)120 degree with each other{hint cos120= -cos60 =1 and half or 1/2 cos 60 =V2

asked by victory on October 23, 2014
43. ## Math Question

To solve this problem, use the Pythagorean Theorem to find the third side. Next, find the other five trigonometric functions of theta (sin, tan, csc, sec and cot). Cos=5/7

asked by Tori on December 2, 2014
44. ## howard

In checking the angles of a section of a bridge support, an engineer finds the expression sin(2 cos-1 0.70). Write a paragraph explaining how the value of this expression can be found without the use of a calculator.

asked by mike on February 25, 2010
45. ## Math Graph

In polar coordinates, the graph r=sin(θ)/cos^2(θ) represents the function y=(a_n)*x^n+(a_(n−1))*x^(n−1)+…+a_0 in Cartesian coordinates, where n is a positive integer and (a_i) are real numbers. What is the value of n?

asked by Crow on June 21, 2013
46. ## Calculus

Sorry... Consider the function f(x) = 8.5 x − cos(x) + 2 on the interval 0 ¡Ü x ¡Ü 1. The Intermediate Value Theorem guarantees that there is a value c such that f(c) = k for which values of c and k? Fill in the following mathematical statements,

asked by Abigail on February 6, 2011
47. ## Calculus

Consider the function f(x)=8.5x−cos(x)+2 on the interval 0¡Üx¡Ü1 . The Intermediate Value Theorem guarantees that there is a value c such that f(c)=k for which values of c and k? Fill in the following mathematical statements, giving an interval with

asked by Abigail on February 5, 2011
48. ## Calculus-HELP!!!!

Show that the function y=c_1 e^x cos(x)+ c_2 e^x sin(x) satisfies the differential equation y''-2y'+2y=0 for any values of c1 and c2, then find the values for those constants that solve the initial value problem y(0)= 1, y'(0)= -1

asked by Elyse on July 2, 2013
49. ## Science

Awake on astring is described by the following equation y=(15cm)cos(3.14/5.0cm x_3.14/12s t.what is the amplitude of this wave?what is its wavelength?what is its period? What is its speed? In which direction does the wave travel

asked by Anonymous on April 30, 2019
50. ## Trignometry

Solve the equation. Express your answer in trigonometric form. x^5-11=0 I know the answer is: 11^1/5(cos α + i sin α) for α = 0°, 72°, 144°, 216°, 288°. But I don't know where to even start working on this problem.

asked by hello on July 1, 2013
51. ## geometry

Let ABC be a right triangle with ACB =90, AC =6 , and BC =2. E is the midpoint of AC , and F is the midpoint of AB . If CF and BE intersect at G , then cos(CGB), in simplest radical form, is ((k square root w)/f) where k , w , and f are positive integers.

asked by Anonymous on March 2, 2013
52. ## Calculus

Find the critical numbers of f, find the open intervals on which the function is increasing or decreasing and use the first derivative test to identify all relative extremes f(x) = 3 + cos^2 x 0

asked by Anonymous on December 9, 2012
53. ## Precalculus

Let C be a circle that passes through the origin. Show that we can find real numbers s and t such that C is the graph of r = 2s*cos(theta + t) I think that I could start by writing it like R^2=(x-h)^2+(y-k)^2 where R is the radius of the circle, but I

asked by Katie on April 18, 2016
54. ## Trigonometry

Use the trig Identities to find the other 5 trig functions. Problem 7.)Tan(90-x)=-3/8 8.)Csc x=-13/5 9.)Cot x=square root of 3 10.)Sin(90-x)=-.4563 11.)Sec(-x)=4 12.)Cos x=-.2351 I need HELP!

asked by Jennifer on January 5, 2010
55. ## math

The terminal side of an angle theta in standard position coincides with the line 2x – y = 0 in Quadrant III. Find cos theta to the nearest ten-thousandth.

asked by james on November 23, 2011
56. ## Polar, Cylindrical, and Spherical Coordinates

Let C be a circle that passes through the origin. Show that we can find real numbers s and t such that C is the graph of r = 2s*cos(theta + t) I think that I could start by writing it like R^2=(x-h)^2+(y-k)^2 where R is the radius of the circle, but I

asked by Katie on April 19, 2016
57. ## trig

choose the expression that is equivalent to the given expression. 2 cos^2 4x-1

asked by tony on June 21, 2013
58. ## calculus =)

find the derivative of g(x)=sin(cos(sin(pi*x)))

asked by Liz on October 7, 2012
59. ## Trig

If tan x = -sq rt3/3 and cos x = -sq rt3/2, the measure of

asked by Patti on April 24, 2015
60. ## Differential Equations

Verify whether the given equation(y=c1-cos(x+c2)) is a solution to this equation[(d^2y/dx^2)^2 + (dy/dx)^2 - 1 = 0].

asked by Alex on April 16, 2017
61. ## Math(Urgent!!!)

sin x / 1-cosx is equivalent to: sin x / 1 + cos x Is this right?

asked by Hannah on March 19, 2010
62. ## triggggg

How does the graph of y = –3cos (2θ + 45°) + 3 differ from the graph of y = cos (θ)

asked by A on April 22, 2019
63. ## math

find the value: lim [4(3)^(1/2)-(cos x+sin x)^5]/(1- x>#/4 sin 2x)

asked by soumitra on September 1, 2014
64. ## calculus

1. Find f '(x) for f(x) = cos (3x3) 2. Find f '(x) for f(x) = ln(x4 + e2x

asked by mock on January 14, 2015
65. ## Trigonometry

cos²a + cos²(a+120°) + cos(a-120°) = 3/2

asked by Kewal on January 12, 2012
66. ## Maths

If sin x = 2/3 and cos y = 3/4, find the exact value of sin ( x + y ).

asked by Fred on April 24, 2018
67. ## Math

If f(u)=u+1/(cos^2u) , u=g(x)=pi(x), x=1/4 , find the derivative of f(g(x)). I can't seem to get this one, step by step please?

asked by Beth on January 2, 2016
68. ## math

how do i solve this? sin of 30 degrees - cos of 45 degrees

asked by kayla on December 12, 2008
69. ## Math

Prove the identities: (sin^2x-1)^2 = cos(2x)+sin^4x

asked by Michael on May 15, 2015
70. ## math

prove 1/sinx-sinx=cos^2xcscx

asked by mike on April 27, 2009
71. ## Calculus

Evaluate cos[2arctan(2)] Need step by step for this one. Thanks

asked by Matg on December 3, 2013
72. ## Trigonometry

verify the identity: 1- (cos^2x)/(1-sinx)= -sinx

asked by Sean on May 30, 2011
73. ## Pre-Calculus

if cos theta =7/13, where 0

asked by Jessica on May 31, 2014
74. ## maths (trigonometry)

how can we calculwte the value of Cot 70 degree+4 cos 70 degree

asked by marley on June 9, 2011
75. ## Math

If sin theta=3/5 THen cos theta wil be

asked by Trignometrical ratios on August 10, 2016
76. ## Trig

solve sin(2 theta)< cos( theta)

asked by maggie on April 19, 2009
77. ## Help!!!

sin x / 1-cosx is equivalent to: sin x / 1 + cos x Is this right?

asked by Hannah on March 19, 2010
78. ## math

find the value: lim [4(3)^(1/2)-(cos x+sin x)^5]/(1- x>#/4 sin 2x)

asked by soumitra on September 1, 2014
79. ## Trigonometric

Given that sinx = 7 /25 pi/2

asked by Matt on November 6, 2012
80. ## Trigonometry

verify the identity: 1-cos^2x/1-sinx= -sinx

asked by Peter on May 30, 2011
81. ## math

find the value: lim [4(3)^(1/2)-(cos x+sin x)^5]/(1- x>#/4 sin 2x)

asked by soumitra on September 1, 2014
82. ## trig

Prove the identity sin (3 pi/2 + x) + sin (3 pi/2 -x) = -2 cos x

asked by rick on February 26, 2008
83. ## Math

sin x / 1-cosx is equivalent to: sin x / 1 + cos x Is this right?

asked by Hannah on March 19, 2010
84. ## calculus

Find the intervals on which the f(x)= cos^2x is concave up and concave down.

asked by amir on March 4, 2012
85. ## Calculus

Find the integral of sin(x) cos(x)/sin^2(x)-4 dx

asked by Maryam on June 5, 2013

sin^6 x + cos^6 x=1 - (3/4)sin^2 2x work on one side only!

asked by hayden on February 23, 2009
87. ## maths---urgently needed

range of sin(siny) +cos(siny)

asked by Anonymous on May 1, 2013
88. ## Algebra2

Help How do I figure out: (cos 40)(cos20) - (sin 40)(Sin 20) Thank you

asked by jeff on May 28, 2010
89. ## Trigonometry

Write cos (lambda + pi/3) as a function of lambda only.

asked by Cyndy on August 3, 2012
90. ## calculus

I'm not sure how to find the limit of this problem :S limit as x -> 0+ (cos(x))^(1/x^2)

asked by James on May 31, 2010
91. ## calc

d/dx (cot(x) / sin(x)) = I got dy/dx= -csc(x) - cos(x)cot(x)

asked by tom on September 18, 2018
92. ## math trignometry

Sin x\2,cos x\2 and tan x\2 for sin x=1\4. x in II quadrant.

asked by Ash on April 22, 2017

Prove the identity: cos^4 x + sin^4 x = 1 - (1/2)sin^2 (2x)

asked by Zack on May 5, 2013
94. ## Math

if I have sin(6x)+cos(6x)how would I write it in terms of sin only?

asked by Kayla on March 22, 2011
95. ## Pre-Calculus

Given Sin(A) = ⅗ and Cos(B) = 8/17 in Quadrant I, find Sin(A+B).

asked by Iris on October 6, 2016
96. ## Math

Solve for: cos (2 theta) = 2 - 2 sin^2 (theta)

asked by Meagan on October 21, 2010
97. ## Pre cal

Find the exact value of Sin ( sin-1. 9/41 - cos-1 (-5/13)

asked by Kk on October 28, 2010
98. ## math

Solve for x if sin2x=cos(x+30) for x [-180;180]

asked by kim on May 19, 2013
99. ## Calculus

How do you integrate [(x^2)(cos(2(x^3)))]? I tried to integrate by parts but I'm going in circles yet again...

asked by Hannah on February 13, 2009
100. ## Trig

find (s+t) given that cos s=1/3 with s in quad I and sin T=-1/2 with t in quad IV

asked by Paige on February 18, 2011