# Homework Help: Math: Trigonometry

## Recent Homework Questions About Trigonometry

**Trig**

Find the area of a triangle whose vertices are A(0,2), B (2,7), C (0,10).

*Thursday, March 23, 2017 by Sue*

**Trig**

Find the area of quadrilateral whose verties are A(0,2), B(2,7), C(6,10), and D (9,-2).

*Thursday, March 23, 2017 by Sue*

**Trig**

what are the intercepts of the graph of f(x)=4cos^2 -3 on the interval [0, 2pi]?

*Monday, March 20, 2017 by Anonymous*

**Math**

Find the exact value of the trig function below. cos2Ø if sinØ = 2/5

*Sunday, March 19, 2017 by Sophie*

**Math**

Find the exact value of the trig function below. cos a/2 if cosa = - 31/49 (assume cos a/2 is negative)

*Sunday, March 19, 2017 by Rachel*

**Trigonometry**

5. If a trig equation has one answer, how many answers will it have? (Provided you do not restrict the domain?) 6. Why are the graphs of the inverse functions restricted to one period of the function? I only need to answer these two to finish my homework and I can't figure out...

*Saturday, March 18, 2017 by Meg*

**Maths Trig**

A 60m long bridge has an opening in the middle and both sides open up to let boats pass underneath. The two parts of the bridge floor rise up to a height of 18 m. Through what angle do they move?

*Saturday, March 18, 2017 by JEHSHDZ*

**Trig**

Convert the polar equation to rectangular form. r=4cos-4sin What I have so far: r^2=4rcos-4rsin x^2+y^2-4x+4y x^2-4x+y^2+4y=0

*Wednesday, March 15, 2017 by Amb*

**Trig**

The vector y has magnitude 5 and direction angle 17°. The vector z has magnitude 3 and direction angle 180°.

*Wednesday, March 8, 2017 by Boyd*

**Trig**

(Tan^2 x) - 2 tan x - 3 / tan x + 1

*Sunday, March 5, 2017 by JB*

**Math - Trig**

Two buildings of equal height are 850 feet apart. An observer on the street between the buildings measures the angles of elevation to the tops of the buildings as 29° and 40°. How high, to the nearest foot, are the buildings? I don't know how to set this up

*Sunday, March 5, 2017 by Scott*

**Trig**

When the angle of elevation of the sun is 61°, a telephone pole that is tilted at an angle of 8° directly away from the sun casts a shadow 20 feet long. Determine the length of the pole to the nearest foot. I'm stuck halfway through this problem, I know how to find all ...

*Sunday, March 5, 2017 by Seth*

**Math Trig**

A ladder 15 m long can so be placed that it will reach a point on a wall 10 m above the ground. By tipping it back without moving its feet, it can be made to reach a point on another wall 8 m above the ground. What is the horizontal distance between the walls?

*Thursday, March 2, 2017 by Mar*

**Urgent--Geometry(trig part)**

So I am new to sine, cosine, and tangent, so I need some help. Just explain it. No need for the answers unless you want to give it to me. :D Let triangle ABC be a right triangle with angleC=90degrees. Given the tangent of one of the complementary angles of the triangle, find ...

*Thursday, March 2, 2017 by Anonymous*

**Trig**

Find all solutions in the interval [0,2pi) 4sin(x)cos(x)=1 2(2sinxcosx)=1 2sin2x=1 2x=1/2 x= pi/6, and 5pi/6 Then since its 2x i divided these answers by 2 and got pi/12 and 5pi/12 However, when i checked the answer key there solutions 13pi/12 and 17pi/12 were included ...

*Sunday, February 26, 2017 by Martha*

**Trig identies, Calculus**

Use the identities cos^2 x + sin^2 x =1 and cos2x=cos^2 x -sin^2 x to show that cos^4 x -sin^4 x = cos2x Im not sure how, I can solve my problem with half angle identities but im not sure where to start with this.

*Saturday, February 25, 2017 by Anon*

**Math - Calc/Algebra/Trig**

I'm trying to find all the points on the graph y=4/3cos^3x-cosx where the tangent line is horizontal. I took the derivative, which gave me: -4cos^2(x)sin(x)+sin(x) Now I need to solve it for x and I'm not sure how. Can you help?

*Thursday, February 16, 2017 by Jamie*

**Calculus Question! ASAP!**

Hello! I have this problem: x(dx)/sqrt(9-x^2) I was wondering why I can't use trig substitution and substitute sqrt(9-x^2) for sqrt(1-sec^2) and having: integral x = 3sin(theta) dx = 3cos(theta)d(theata) integral 3sin(theta)(3cos(theta))/3cos(theta) having the 3cos(theta) ...

*Wednesday, February 15, 2017 by Lucy*

**Trig**

Solve for t algebraically: inverse cos(t) = inverse sin(t). Where do I start?

*Monday, February 6, 2017 by Anonymous*

**Alg/Trig**

If h= -16t^2 + 112t represents the height of a rocket, in feet, t seconds after it was fired, when will the rocket hit the ground? (Hint: The rocket is on the ground when h equals=0).

*Sunday, February 5, 2017 by Sydney*

**Trig Practice**

Find the exact value of sinA where a=9 and b=10 and angle C is a right angle. a. sin A= 9/sqrt 181, cos A= sqrt 181/10 b. sin A= sqrt 181/9, cos A= 10/sqrt 181 c. sin A= 9/sqrt 181, cos A= 10/sqrt 181 d. sin A=sqrt181/10, cos A= 9/sqrt 181

*Friday, February 3, 2017 by Anonymous*

**trig**

in triangle QRS, q=10.2m, r=20.5m, s12.8m..Solvetriangle QRS by determining the measurements of each degree to the nearest tenth of a degree

*Monday, January 30, 2017 by dee*

**Trig**

4x+y=0, x≥0 help finding Sin, Cos, Tan for this

*Thursday, January 26, 2017 by Ashley*

**Trig**

can sec θ = negative 5

*Thursday, January 26, 2017 by Ashley*

**trig**

sin, cos, and tan for −5x + y =0, x is less than or equal to 0

*Thursday, January 26, 2017 by Ashley*

**Trig**

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

*Thursday, January 26, 2017 by Ashley*

**Geometry/Trig**

A painter is placing a ladder to reach the third story window, which is 18 feet above the ground and makes an angle with the ground of 80°. How far out from the building does the base of the ladder need to be positioned? Round your answer to the nearest tenth. The base of the...

*Wednesday, January 25, 2017 by Sosa*

**Geometry / Trig**

What is the area of a regular hexagon with a distance from its center to a vertex of 1 cm? (Hint: A regular hexagon can be divided into six equilateral triangles.) hex The area of the regular hexagon is _____ ?

*Wednesday, January 25, 2017 by Sosa*

**trig**

Reiny 2+1/3*tan(theta)=2 How do you get 0? Thanks for your help.

*Tuesday, January 24, 2017 by Sally*

**Trig**

2+1/3tan(theta)=2 I know that tan=0 0,180 But i don't know how to figure it out. Please help.

*Tuesday, January 24, 2017 by Sally*

**Trig**

4=5+cos(theta)

*Tuesday, January 24, 2017 by Sally*

**Trig**

Thank you Steve for all your help.

*Tuesday, January 24, 2017 by Sally*

**Trig**

Solve equation for 0 less than or equal to theta less than 360. 3-1/5*tan(theta)=16/5

*Tuesday, January 24, 2017 by Sally*

**trig**

Brian is riding a Ferris wheel. The wheel has a radius of 25 feet, and at his lowest point, Brian is 8 feet off the ground. Brian times how long it takes to travel from the lowest point to the highest point and finds that it takes 8 seconds. Write a sinusoidal equation to ...

*Saturday, January 21, 2017 by bobby*

**Pre-cal/trig**

A dog is attached to a 21-foot rope fastened to the outside corner of a fenced-in garden that measures 18 feet by 22 feet. Assuming that the dog cannot enter the garden, compute the exact area that the dog can wander. I'm confused as to how they want me to solve this...

*Wednesday, January 18, 2017 by Aiden*

**Trig**

An isosceles triangle has a height of 12.5 m (measured from the unequal side) and two equal angles that measure 55°. Determine the area of the triangle. Split in half the triangle is a right triangle, so it's three angles are 90%, 55% and 70%. I'm still not sure how to find ...

*Tuesday, January 10, 2017 by R*

**Trig/PreCalc**

Find a parametrization for the line segment with endpoints (5,2) and (-2, -4).

*Tuesday, January 10, 2017 by William*

**Trig/PreCalc**

Use an algebraic method to eliminate the parameter and identify the graph of the parametric curve. x=5-3t y=2+t -1<-x-<3

*Tuesday, January 10, 2017 by Diane*

**Trig/PreCalc**

Find the interior angles of the triangle with vertices (-4,1), (1,-6), and (5,-1)

*Tuesday, January 10, 2017 by Maria*

**Trig/PreCalc**

An airplane is flying on a compass heading of 160 degrees at 425 mph. A wind is blowing with the bearing 200 degrees at 75 mph. Find the actual speed and direction of the airplane.

*Tuesday, January 10, 2017 by Susan*

**trig**

A person is standing 90 feet away from the Space Needle. The person looks up at the Space Needle at an angle of elevation of 81 degrees. The distance from the floor to the person's eye level is 5 feet. What must be the height of the Space Needle?

*Tuesday, January 10, 2017 by Vanni*

**Trig**

Let n be a fixed positive integer. Describe all solutions of sin(n theta) = 1/2 I know that the solutions would be (π/6)/n+(2πx)/n and (5π/6)/n+(2πx)/n ? How do I 'describe'

*Sunday, January 8, 2017 by Ryan*

**Trig**

Given: sin x = 4/5, 0 < x < π/2 sin y = 5/13, π/2 < y < π Find the exact value of sin(x + y) I presume I'm supposed to use the sum and difference formulas but I'm not sure how to get the exactly value of cos x or cos y

*Wednesday, January 4, 2017 by R*

**trig prove plz anyone help**

Prove that: x - tan^-1(x) = tan^-1{(tanx - x)/(xtanx + 1)} plz help

*Tuesday, December 27, 2016 by ...*

**Math - Trig / Pre - Calc**

Standard form of hyperbola: Hyperbola: Vertices: (9,9), (9, -7) Foci: (9, 1 + 4 sqrt 13), (9, 1 - 4 sqrt 13)? Standard form Ellipse: vertices: (2 sqrt 10, -10), (-2 sqrt 10, -10) foci: (sqrt 30, -10), (-sqrt 30, -10)?

*Wednesday, December 21, 2016 by Lilly*

**Math trig**

Two towers 50 meters apart from the top of the shorter tower to the top of the taller tower 43 degree elevation, depression from the top of shorter tower to the bottom of the taller tower is 36 degrees what is the height of each tower?

*Tuesday, December 20, 2016 by Shania*

**Trig Question**

Find solutions of the following equation which lie in the interval [0,2pi): 6cos(3theta)/(2)+3=0

*Tuesday, December 13, 2016 by Amy*

**Trig identities**

Has a negative -5/13 Steve. If angles x and y are in the same quadrant and sin x =3/5 and cos y= -5/13 determine the value of sin (x-y)

*Thursday, December 8, 2016 by Luke*

**Trig**

Cicero has a population of 6200 people and is growing at a rate of 8% per year . Mattydale has a population of 8750 and is growing at a rate of 6% per year create and equation solve the problem and in how many years to the nearest year will Cicero have a greater population ...

*Tuesday, December 6, 2016 by Christian*

**trig**

The rectangular coordinates of a point are given (0,-6). Find polar coordinates of the point such that r greater than 0 and 0 less than or equals theta less than 2pi. how to solve this damon please help me

*Monday, November 28, 2016 by Asfand*

**trig**

The rectangular coordinates of a point are given (-5,-5root3). Find polar coordinates of the point. Express theta in radians.

*Monday, November 28, 2016 by Asfand*

**Math**

Consider ∠C such that sin C = 7/25 a) What are the possible quadrants in which ∠C may lie? b) If you know that cos C is negative, how does your answer to part a) change? c) Sketch a diagram to represent ∠C in standard position, given that the condition in part b) is true...

*Tuesday, November 22, 2016 by Katie*

**Trig**

What are the focus and directrix of the parabola represented by the equation:8(y-6)=(x+2)squared?

*Monday, November 21, 2016 by Emily*

**Trig**

From a point A, 30 meters from the base of a building B, the angle of elevationto the top of the building C is 56 degrees. The angle of elevation to the top of flagpole D on top of the building is 60 degrees. Find the length of flagpole CD

*Sunday, November 20, 2016 by Ellie*

**Trig**

Find the exact value of the trigonometric function given that sin u=3/5 and cos v=-8/17. Both u and v are in quadrant II. Tan (u+v)

*Monday, November 14, 2016 by Lynn*

**Trig**

find the angle between u=7i+2j and v=-4j

*Wednesday, November 9, 2016 by Iris*

**trig help**

simplify cosec40(sin40+sin80+cos120) help step

*Monday, November 7, 2016 by Anonymous*

**trig help**

simplify cosec40(sin40+sin80+cos120) help step

*Monday, November 7, 2016 by Anonymous*

**trig**

A communication tower is 34m tall. Jane stands somewhere in front of the tower to the right and measures the angle of elevation to be 70 degrees. Bill stands somewhere in front of the tower to the left and measures the angle of elevation to be 50 degrees. How far apart are ...

*Sunday, November 6, 2016 by Anonymous*

**Trig**

find all solutions of 2sinx=1-2cosx in the interval from 0 to 360

*Tuesday, November 1, 2016 by Anonymous*

**Pre-Calc/ Trig**

Find the sum of the three smallest positive values of theta such that 4(cos^2)(2theta-pi) =3. (Give your answer in radians.) LaTEX: Find the sum of the three smallest positive values of $\theta$ such that $4\cos^2(2\theta-\pi) =3$. (Give your answer in radians.)

*Monday, October 31, 2016 by Steve Ho*

**Physics algebra and trig**

A pair of fuzzy dice is hanging from the rearview mirror of a race car. As the car accelerates smoothly, the strings of the dice are tilted slightly toward the rear of the car. From the perspective of the driver, which one of the following statements is true, if the dice are ...

*Thursday, October 20, 2016 by Kyle*

**Trig**

Write 3theta - sin 4theta as a product.

*Monday, October 17, 2016 by Sade*

**Trig**

Use the half-angle formula to simplify (sin4theta)/(1+cos4theta)

*Monday, October 17, 2016 by Sade*

**math trig**

how do you solve arcsin(3/5) without a calculator?

*Sunday, October 16, 2016 by help*

**Trig**

If angle A is 45 degrees and angle B is 60 degrees. Find sin(A)cos(B), find cos(A)sin(B), find sin(A)sin(B), and find cos(A)cos(B) The choises for the first are: A. 1/2[sin(105)+sin(345)] B. 1/2[sin(105)-sin(345)] C. 1/2[sin(345)+cos(105)] D. 1/2[sin(345)-cos(105)] You don't ...

*Saturday, October 8, 2016 by Sade*

**Trig**

Given tan(A) = 2 and A is in Quadrant I, find tan(2A). A. -1/3 B. 2/3 C. -4/3 D. -2/3

*Friday, October 7, 2016 by Sade*

**Trig**

Given tan(A) = 2 and A is in Quadrant I, find cos(2A). A. 0 B. 1 C. 1/2 D. -3/5

*Friday, October 7, 2016 by Iris*

**Trig**

Just confused. Given tan(A) = 2 and A is in Quadrant I, find sin(2A). A. 0 B. 1 C. 1/2 D. 4/5

*Friday, October 7, 2016 by Iris*

**Trig**

Given Tan(A) = 5 in Quadrant III and Sin(B) = ⅔ in Quadrant II, what is the Quadrant of A-B?

*Thursday, October 6, 2016 by Sade*

**Trig**

Given Tan(A) = 5 in Quadrant III and Sin(B) = ⅔ in Quadrant II, find Cos(A-B).

*Thursday, October 6, 2016 by Sade*

**Trig**

Given Tan(A) = 5 in Quadrant III and Sin(B) = ⅔ in Quadrant II, find Sin(A-B).

*Thursday, October 6, 2016 by Sade*

**Math (Trig Review)**

Evaluate the expression without using a calculator (Make a sketch of a right triangle) tan(arccot 2) Thanks in advance! I'm trying to refresh my memory of these kinds of problems and I'm having trouble on how to solve this problem

*Friday, September 30, 2016 by Ray*

**Trig**

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

*Wednesday, September 28, 2016 by Sarah*

**math trig**

A Ferris wheel with a diameter of 37 meters rotates at a rate of 4 minutes per revolution. Riders board the Ferris wheel 4 meters above the ground at the bottom of the wheel. A couple boards the Ferris wheel and the ride starts. Write a formula for the height of the couple t ...

*Wednesday, September 28, 2016 by help*

**maths trig need help**

show that sinx/(1-cotx)+cosx/(1-sinx)=sinx+cosx thanks

*Tuesday, September 27, 2016 by rap*

**maths trig**

A flag in the form of an equilateral triangle is connected to the tops of 2 vertical poles. One of the pole has a length of 4 and the other pole has a length of 3. You also know that the third vertex touches the ground perfectly. Calculate the length of a side

*Friday, September 23, 2016 by samson*

**Trig**

Can someone check my answers? Find # of triangles possible: <A=44.3, a=11.5, b=7.7 ... 2 triangles, B=~27.9 or B=~152.1 <A=29.3, b=20.5, a=12.8 ... 2 triangles, B=~51.6 or B=~128.4

*Wednesday, September 21, 2016 by K*

**Trig**

A ship leaves port and sails at a bearing of 124degrees. Another ship leaves the same port, at the same time, sailing at a bearing of 74degrees. When both ships are 80 miles from the port, how far are they from each other?

*Sunday, September 11, 2016 by Adrienne*

**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 isn't an option? ...

*Tuesday, September 6, 2016 by Lyss*

**Algebralgebrad**

Trig ientities

*Sunday, September 4, 2016 by yaga*

**Trig**

if sin(x)=-0.5 and x is in the third quadrant, find x

*Saturday, August 20, 2016 by Jason*

**trig**

if sec theta =sqrt -20/3 state the exact value of tan theta

*Tuesday, July 26, 2016 by Anonymous*

**MAth Trig**

Find the diameter of a circle with an arc length of 32 cm and a subtended angle of 72 degrees

*Tuesday, July 26, 2016 by Anonymous*

**MATH**

Solve the integral using trig substitution (1/((x)(x^2+1)))dx

*Sunday, July 24, 2016 by ANON*

**MATH**

Integrate 1/(x(x^2+1)) dx using trig substitution

*Sunday, July 24, 2016 by ANON*

**Math - Trig**

The depth of water, h, in metres at time t, in hours, is given by the formula: h(t)=7.8+3.5sin[pi/6(t−3)]. Its a 24 hours period and t=0 is midnight. Provide an algebraic solution to determine the time(s) of day, the water reaches the depth of 10.29 m i got one time 4.51...

*Friday, July 22, 2016 by Sherry*

**Math - Trig**

The equation given below models the average monthly temperature (˚C). t denotes the number of months with t=1 representing January. During which months is the average monthly temperature 12.5˚C? 𝑇(𝑡) = 12.5 + 15.8sin (𝜋/6 (𝑡) −2...

*Wednesday, July 20, 2016 by Anonymous*

**Math - Trig**

A hamster enters a wheel at the lowest point and begins to run . The height of point R (in the diagram below) above the ground is given by the function ℎ(𝑡) = −17.5 cos ( 2pi/3 𝑡) + 19, where ℎ is height in centimeters and 𝑡 is time in...

*Wednesday, July 20, 2016 by Anonymous*

**Math - Trig**

Solve for exact or to 1d.p of x E [0 ,2pi] 4cos^2x-3

*Monday, July 18, 2016 by Anonymous*

**Pre-Cal**

[Note: I'm still having issues with identities with regard to trig] Verify the Trig. identities: (a). cot(x+y)=(cotxcoty-1)/(cotx+coty) (b). sin0(cot0+tan0)=sec0 [Note: 0=theta symbol]

*Monday, July 11, 2016 by Amber*

**trig**

what is the exact value of tan 105 degrees

*Wednesday, June 29, 2016 by fortue*

**trig**

If a ship leaves port at 9:00 a.m. and sails due south for 3 hours at 14 knots, then turns N 60° E for another 2 hours, how far from port is the ship?

*Friday, June 24, 2016 by need help*

**trig**

If a ship leaves port at 9:00 a.m. and sails due north for 3 hours at 12 knots, then turns N 30° E for another hour, how far from port is the ship?

*Wednesday, June 22, 2016 by lejla*

**Math (Trig)**

Suppose the point A is on a circle of radius 6 with an angle of 240 degrees. Find the value of the coordinates of this point. Round your results to 3 decimal places. So in this case, x=rcos(theta) y=rsin(theta) x=6cos(240) y=6sin(240) Rounding to 3 decimal places: x=-3 y=-5....

*Tuesday, June 7, 2016 by Giovanni*

**Math (Right Triangle Trig)**

Suppose tan(theta)=5/7 and theta belongs to Quadrant III, find the exact value of sec(theta)? I already took the steps to solve this problem but I am confused if whether or not sec(theta)is positive or negative sqrt(74)/7 Any help is greatly appreciated!

*Sunday, June 5, 2016 by Giovanni*

**Trig**

6. To win a javelin throwing competition, your last throw must travel a horizontal distance of at least 100 feet. You release the javelin at a 40° angle with an initial speed of 71 feet per second. Do you win the competition? Justify your answer

*Friday, June 3, 2016 by Noah Ahmed*

**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.

*Wednesday, June 1, 2016 by Jack*

**Trig**

If sin(theta) = 3/7, what is sin (pi/2 - theta)?

*Thursday, May 19, 2016 by Anonymous*

**Math (Trig)**

Convert the Cartesian coordinate (-1,2) to polar coordinates, 0≤θ<2π I know r is sqrt(5) but how would I find theta between 0 and 2pi? Thanks in advance!

*Monday, May 16, 2016 by Giovanni*