Circles Definition and 307 Threads

I have just started curiously thinking about this. The trig functions cos and sin give the (x,y) coordinates of the unit circle. How would i go about using the trig functions to finding (x,y) coordinates of an arbitrary circle? What I am saying is, the cos and sin only work for the circle x^2...

Dear All, I need to know the area of the crescent created by overlapping circles;e.g. a circle radius 50µm overlapped by an equal circle with its centre 10µm to the left. Any help you can offer would be gratefully received, thanks.

There are an infinite number of radii within any given circle, are there also an infinite number of circles within a circle as shown in the attached image ?

Homework Statement Show that the centers of the circles passing through the points (3,2) and (6,3) are located on the line 3x+y=16. Two of these circles touch the line x+2y=2. Find the equation of both these circles. 2. Homework Equations The general equation of curves (circles...

http://science.uniserve.edu.au/school/sheets/fairycircle.html I site i stumbled across, and just wondered if an explanation has been found.

kay had a question which i got zero on and now trying to figure out how the hell to do the question. Given x^2 + (y-1)^2 =1 rotated about the x-axis. if i could get the solution so i can review it so i can have a better idea how to do it on the mid term. Hint:, I was told to do with...

Here's the question. A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to twice her weight as she goes through the dip. If r=20.0 m, how fast is the roller coaster...

This has been bugging me for a while and I thought that you guys might know an answer. Awhile ago I realized that there is a direct relationship between the radius (as in the distance between a corner and the center) squared and the area of any regular polygon with the same number of sides. For...

http://www.olemiss.edu/mathed/geometry/tight.gif To determine the shortest rope that can be wrapped around the two circles any ideas? i have forgotten everything about geometry. My nephew asked me this

1.what is the equation of the largest circle that can be incribed in a square of side length 9 units, if the diagonals of the square intersect at (-1,3). where the radious is 9, but the ansewer in wrong *** 2.Todd is flying his radio-controilled airplane abouve the ground in a circular path...

I understand how trigonometry is related to the Unit Circle, but is there any way I can relate the same concept to circles with a radius other than 1? Thanks in advance. :biggrin:

i have a couple questions which i didnt want to continue on posting in the other thread or else it would get extremely hard to follow. 1. recall that the Intersecting Secants Property states that if two secants AB and CD intersect at an external point P, then PA x PB = PC x PD. well, i need...

1. A, B and C are points on the circumference of a circle, centre O, and ∠BAC=115°. Calculate the number of degrees in ∠OBC. I drew a diagram but could not come up with anything primarily because ∠BAC and centre O lie on opposite sides of chord BC (draw a quick diagram if you don't know what...

Suppose you ride a bicycle on a horizontal surface in a circle with a radius of 20 m. The resultant force exerted by the road on the bicycle (normal force plus frictional force) makes an angle of 15 degs with the vertical. a. What is your speed? b. If the frictional force is half its maximum...

is it possible to solve cos pi(t) + sin pi(t) = 0 for determining the value of pi(t)?? pls help

Hey, my Q is: "Integrate f(x, y) = Sqrt(x^2 + y^2) over the region in the x-y plane bounded by the circles r = 1 and r = 4 in the upper half-plane". Well, I firstly sketched out the region I get as my area in the x-y plane. I deduced that the ranges for x and y are: 0 <= x <= 4 Sqrt[1...

Hello, i am having difficulty on a question involving chords i believe. what i have so far is: the length of CA is 17. therefore the length of CB is also 17 due to the fact that it is the radius of the first circle. the length of AD is 10. Therefore BD is also 10 because it is the radius...

consider the 3 great circles C1,C2,C3 with respective normals (0,-1,1) (1,0,1) (1,1,0), and let f = Rc3Rc2Rc1 is f orientation preserving or orientation reversing. can i make a matrix using the normals... then calculate the determinate of A. and if its negative then its reversing and if...

what is the formula to find a sector in a circle? so I'm given the radius and the arc of angle 60 degrees. To find the area in that arc, the forumla is something along the lines of: A=\frac{r^2}{2} * arc so... A=\frac{r^2}{2} * \frac{\pi}{3} is this right?

As someone who only studied first year physics and maths and have taken no interest in it since than I was rather surprised to wake up one morning and realize along with 99.5% of the population that I really had no idea how the planets orbits worked beyond the vague word ellipse which I didn't...

I have two circles intersecting at 2 points in 2d space. Let's call them cirles O1 and O2. On O1, I have 3 points A,B and D. On O2, I have a point C. Given co-ords of only 3 points A, B, C, and value of angle ADC (alpha), how can I find out the coord values x,y of point D ? Thanks :blushing:

If I take a perfectly rigid disk 10 miles in diameter and set it spinning at a constant speed. Is the constant acceleration an object experiences riding 5 feet from the center the same as it would be if it were 5 miles from the center? I know many other things would be different but I mean the...

How many orders can we have of 3 red roses and 3 white roses arranged in a circle? Apparently the answer is 10 - but how do yiou work it out? I know that in a circle of "n" different objects the number of different arrangements is (n-1)!, but what about the repeats? If anyone could explain a...

I'm looking to find someone who can help me with my problem... My problem is that I need to remove material from linear tapered strips with a 1 inch round cutter. The circles need to connect to each other at half the section depth over the entire length of the strip --->...

I know that crop circles have been discussed to death but, has all the data gleaned from the investigations of these anomalies shown that they are hoaxes ie the node explosions?

I just want to make sure that I am doing this right or if I am on the right track. To find a map f :R ---> R so that ker f ={(x,y): x^4=y^4} pi_R: (x,y) ---> {(x,y): x^4=y^4} pi_R: x ---> {R(x): x^4 is an element in X} pi_R: Y ---> {R(y): y^4 is an element in Y} Define f: R x R --->...

circles... and pie ok so i found this site and I am learning about circles now :) http://www.mathgoodies.com/lessons/vol2/circumference.html it says pie is 3.14 which is what you get when you divide the outer measurement of the circle by the diameter (pie being 3.14 as per his homework)...

I need to know the names of theorems related to the following two problems: 1. What is the maximum sum less than 1 but more than 0 that can be formed from \frac{1}{p} + \frac{1}{q} + \frac{1}{r}, where p, q and r are positive integers? 2. What is the maximum perimeter and area of an...

If sin theta = \frac {-4} {7} and \frac {3 pi} {2} < theta < 2 pi then determine the exact value of \frac {1} {cot (theta)} I don't know where to start I know to set up a circle with a cartesian plane but what am I supposed to do? :rolleyes:

Picture two indentical circles with their radii overlapping. They form an intersection, what is the area of their intersection? I solved it the calculus route and it can be solved geometrically. Have fun.

A circle with the radius R cuts the centers of circles with the radius r that does mearly touch each other, What is the equation for the number of circles in the circle?

Hey ppl, Could anyone help me with this: what is the ratio of the areas of the circumscribed and inscribed circles of a regular hexagon? how do I go about working it out from first principles? Cheers, joe

Sorry to bother you guys.. but if there is someone out there that is good at math and wouldn't mind helping me.. could you aim me sn:"euphoriet" thanks.

Hi All, I went to this website where someone wants to know how to calculate the area of some intersecting circles in this diagram on the page. I took Geometry and Trig but unfortunately my brain turned to mush over the summer and I can't remember how to do this, can someone here tell me how I...

I'm just introducing myself to coordinate geometry in the xy plane of cirlces. Here's a question I'm having trouble with: Q11: The line with equation y=mx is a tangent to the circle with equation x^2 + y^2 - 6x - 6y + 17 = 0. Find the possible values of m. At first i thought i'd try...

Here's an interesting problem (interesting to me, at least) that my professor gave me last year (outside of class...it had nearly nothing to do with the subject we were studying). It's of two parts: The first part is fairly simple. Suppose you have the graph f(x)=x^2. What is the radius of...

Does anyone here take some crop cirlces seriously? http://paranormal.about.com/library/weekly/aa021802a.htm

What you guys think of crop circles? The latest one are astonishing and I don't imagine people on the ground hoaxing them. Maybe we are being manipulated by mass media and those crop circles are produced using computers by Hollywood specialists? Earliest crop circles I admit were made by...

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Hey, I’d appreciate some help with these questions: (c) Find the centre and radius of the circle x^2 + y^2 – x – y – 12 = 0. Find the equations of the tangent to this circle which are parallel to the line 7x – y = 0. Ok, so I found the line has a slope of 7, and the circle has a...

Trig Question Any ideas on solving this problem? The question reads... [FONT=Arial]Four mutually tangent circles are shown. Find the radius of the shaded circle. See attachment. Any help will be appreciated. :confused:

I am not very well versed in math, but I do have some idea, would this theorem be correct? Basis Step: x is an element of the universal set. In other words, you could say that the number 5 is an element of N(the set of natural numbers), and it is also in the set of R (the set of Real...

The "Golden Spiral" - Calculating intersections with circles. Hello all, I am working on a program that graphs the Golden Spiral and then lays a set of circles on top of it. I was curious to know if there is a formula I can use to figure out the x, y coordinates where a circle of a given radius...

Two identical uniform spheres, each weighing 75 N are at rest on the bottom of a fixed rectangular container. The line of centers of the spheres makes an angle of 35* with the horizontal. Find the forces exerted on the spheres by the container bottom, the container sides as well as the force...

Heya Folks, First I would like to apologize for my bad English - I live in Israel and our mother toungue is Hebrew here, I'll try my best though.. Now I don't know how you call what we call Straght-Line Electricity Circles but basically I mean AC just not alternative ;) Anyways my...

Imagine a circle of given radius. Construct all circles of equivalent radii whose centers constitute that initial circumference. Can you derive a probability density that describes the overall distribution of points from those resultant circles?

In school, I'm doing this thing called moment of inertia given by the formula I = \int y^2 dA If the object being solved for is a rectangle where the base of it is parallel to the x axis, dA is equal to xdy. From there, the integration is easy. If the object to solve the integration for is...

Imagine a two dimensional universe, a plane. We take two perfect circles on this plane; they are uncompressable, being elementary particles or some such thing (whatever they are, the important thing is that they cannot be compressed). We take these two circles and set them on a collision...

Does anyone know it, or have good guesses? I'm not particularly interested in the subject per se, but I find it strange that the skeptical explanation (that it is a hoax) is as phoney as the claims that ET's do it. As far as I can tell no one seems to know what is going on, and yet everyone...

a man jumps out of a plane w/ a parachute at 1000m above a spherical planet (point A). He sees a satellite rise at the eatern horizon. Standing 2 m above surface of the planet (equator)(point B), the satellite re-appears 1.5 minutes after he saw it at 1000 m above sea level. From this point, the...