37 articles trouvés pour ce sujet.
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The maximum area of a garden |
2021-04-28 |
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Lexie pose la question : suppose you want to make a rectangular garden with the perimeter of 24 meters.
What's the greatest the area could be and what are the dimensions? Penny Nom lui répond. |
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Maximizing the volume of a cone |
2020-05-18 |
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Ella pose la question : Hello, this is question - 'If you take a circle with a radius of 42cm and cut a sector from it,
the remaining shape can be curled around to form a cone. Find the sector
angle that produces the maximum volume for the cone made from your circle.' Penny Nom lui répond. |
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Form a square and a triangle from a wire |
2020-04-08 |
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Raahim pose la question : 2. A 2 meter piece of wire is cut into two pieces and once piece is bent into a square and the other is bent into an equilateral triangle. Where should the wire cut so that the total area enclosed by both is minimum and maximum? Penny Nom lui répond. |
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The maximum volume of a cone |
2019-07-14 |
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A student pose la question : find the maximum volume of a cone if the sum of it height and volume is 10 cm. Penny Nom lui répond. |
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The maximum area of a rectangle with a given perimeter |
2017-06-02 |
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Bob pose la question : How would I go about finding the maximum area of a rectangle given its perimeter (20m, for example)? Penny Nom lui répond. |
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A Max/Min problem with an unknown constant |
2016-01-17 |
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Guido pose la question : Question:
The deflection D of a particular beam of length L is
D = 2x^4 - 5Lx^3 + 3L^2x^2
where x is the distance from one end of the beam. Find the value of x that yields the maximum deflection. Penny Nom lui répond. |
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A calculus optimization problem |
2015-05-14 |
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Ali pose la question : Given an elliptical piece of cardboard defined by (x^2)/4 + (y^2)/4 = 1. How much of the cardboard is wasted after the largest rectangle (that can be inscribed inside the ellipse) is cut out? Robert Dawson lui répond. |
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Constructing a box of maximum volume |
2015-04-14 |
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Margot pose la question : I need to do a PA for maths and I'm a bit stuck.
The PA is about folding a box with a volume that is as big as possible. The first few questions where really easy but then this one came up.
8. Prove by differentiating that the formula at 7 does indeed give you the maximum volume for each value of z. Penny Nom lui répond. |
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A cone of maximum volume |
2015-03-16 |
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Mary pose la question : I have to use a 8 1/2 inch by 11 inch piece of paper to make a cone that will hold the maximum amount of ice cream possible by only filling it to the top of the cone. I am then supposed to write a function for the volume of my cone and use my graphing calculator to determine the radius and height of the circle. I am so confused, and other than being able to cut the paper into the circle, I do not know where to start. Thank you for your help! -Mary Robert Dawson lui répond. |
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Largest cone in a sphere |
2015-01-15 |
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Alfredo pose la question : What is the altitude of the largest circular cone that may be cut out from a sphere of radius 6 cm? Penny Nom lui répond. |
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The popcorn box problem |
2013-11-07 |
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Dave pose la question : We know that calculus can be used to maximise the volume of the tray created when cutting squares from 4-corners of a sheet of card and then folding up.
What I want is to find the sizes of card that lead to integer solutions for the size of the cut-out, the paper size must also be integer. EG 14,32 cutout 3 maximises volume as does 13,48 cutout 3.
I have done this in Excel but would like a general solution and one that does not involve multiples of the first occurence, as 16, 10 cutout 2 is a multiple of 8,5 cutout 1. Walter Whiteley lui répond. |
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Maximize the volume of a cone |
2013-10-09 |
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Conlan pose la question : Hi I am dong calculus at school and I'm stumped by this question:
A cone has a slant length of 30cm. Calculate the height, h, of the cone
if the volume is to be a maximum.
If anyone can help me it would be greatly appreciated.
thanks. Penny Nom lui répond. |
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Maximize profit |
2013-01-19 |
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Chris pose la question : A firm has the following total revenue and total cost function.
TR=100x-2x^2
TC=1/3x^3-5x^2+30x
Where x=output
Find the output level to minimize profit and the level of profit achieved at this output. Penny Nom lui répond. |
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A max/min problem |
2012-12-14 |
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bailey pose la question : A right angled triangle OPQ is drawn as shown where O is at (0,0).
P is a point on the parabola y = ax – x^2
and Q is on the x-axis.
Show that the maximum possible area for the triangle OPQ is (2a^3)/(27) Penny Nom lui répond. |
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A maximization problem |
2012-04-09 |
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Nancy pose la question : After an injection, the concentration of drug in a muscle varies according to a function of time, f(t). Suppose that t is measured in hours and f(t)=e^-0.02t - e^-0.42t. Determine the time when the maximum concentration of drug occurs. Penny Nom lui répond. |
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A max min problem |
2012-02-26 |
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Christy pose la question : Hello, I have no idea where to start with this question.
Bob is at point B, 35 miles from A. Alice is in a boat in the sea at point C, 3 miles from the beach. Alice rows at 2 miles per hour and walks at 4.25 miles per hour, where along the beach should she land so that she may get to Bob in the least amount of time? Penny Nom lui répond. |
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Lost in the woods |
2012-01-12 |
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Liz pose la question : I am lost in the woods. I believe that I am in the woods 3 miles from a straight road. My car is located 6 miles down the road. I can walk 2miles/hour in the woods and 4 miles/hour along the road. To minimize the time needed to walk to my car, what point on the road should i walk to? Harley Weston lui répond. |
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Designing a tin can |
2011-03-31 |
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Tina pose la question : A tin can is to have a given capacity. Find the ratio of the height to diameter if the amount of tin ( total surface area) is a minimum. Penny Nom lui répond. |
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What is the maximum weekly profit? |
2010-10-10 |
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Joe pose la question : A local artist sells her portraits at the Eaton Mall.
Each portrait sells for $20 and she sells an average of 30 per week.
In order to increase her revenue, she wants to raise her price.
But she will lose one sale for every dollar increase in price.
If expenses are $10 per portrait, what price should be set to maximize the weekly profits?
What is the maximum weekly profit? Stephen La Rocque and Penny Nom lui répond. |
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Maximizing the volume of a cylinder |
2010-08-31 |
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Haris pose la question : question: the cylinder below is to be made with 3000cm^2 of sheet metal. the aim of this assignment is to determine the dimensions (r and h) that would give the maximum volume.
how do i do this?
i have no idea. can you please send me a step-to-step guide on how t do this?
thank you very much. Penny Nom lui répond. |
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A max min problem |
2010-08-19 |
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Mark pose la question : a rectangular field is to be enclosed and divided into four equal lots by fences parallel to one of the side. A total of 10000 meters of fence are available .Find the area of the largest field that can be enclosed. Penny Nom lui répond. |
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Maximize the floor area |
2010-07-07 |
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shirlyn pose la question : A rectangular building will be constructed on a lot in the form of a right triangle with legs
of 60 ft. and 80 ft. If the building has one side along the hypotenuse,
find its dimensions for maximum floor area. Penny Nom lui répond. |
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A max/min problem |
2010-06-12 |
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valentin pose la question : What is the maximum area of an isosceles triangle with two side lengths equal to 5 and one side length equal to 2x, where 0 ≤ x ≤ 5? Harley Weston lui répond. |
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An optimization problem |
2010-05-23 |
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Marina pose la question : Hello, I have an optimization homework assignment and this question has me stumped..I don't even know A hiker finds herself in a forest 2 km from a long straight road. She wants to walk to her cabin 10 km away and also 2 km from the road. She can walk 8km/hr on the road but only 3km/hr in the forest. She decides to walk thru the forest to the road, along the road, and again thru the forest to her cabin. What angle theta would minimize the total time required for her to reach her cabin?
I'll do my best to copy the diagram here:
10km
Hiker_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _Cabin
\ | /
\ | /
f \ 2km /
\ | /
theta \___________________________ /
Road Penny Nom lui répond. |
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A max min problem |
2010-04-06 |
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Terry pose la question : The vertex of a right circular cone and the circular edge of its base lie on the surface of a sphere with a radius of 2m. Find the dimensions of the cone of maximum volume that can be inscribed in the sphere. Harley Weston lui répond. |
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A rectangular pen |
2009-08-13 |
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Kari pose la question : A rectangular pen is to be built using a total of 800 ft of fencing. Part of this fencing will be used
to build a fence across the middle of the rectangle (the rectangle is 2 squares fused together so if you can
please picture it).
Find the length and width that will give a rectangle with maximum total area. Stephen La Rocque lui répond. |
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A maximum area problem |
2009-01-13 |
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Kylie pose la question : Help me please! I don't know how or where to start and how to finish.
The problem is: A window has the shape of a rectangle surmounted by a semicircle. If the perimeter of the window is 15 ft., find the dimensions that will allow the maximum amount of light to enter. Harley Weston lui répond. |
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Taxes in Taxylvania |
2008-10-22 |
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April pose la question : Taxylvania has a tax code that rewards charitable giving. If a person gives p% of his income to charity, that person pays (35-1.8p)% tax on the remaining money. For example, if a person gives 10% of his income to charity, he pays 17 % tax on the remaining money. If a person gives 19.44% of his income to charity, he pays no tax on the remaining money. A person does not receive a tax refund if he gives more than 19.44% of his income to charity. Count Taxula earns $27,000. What percentage of his income should he give to charity to maximize the money he has after taxes and charitable giving? Harley Weston lui répond. |
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Maximize revenue |
2008-10-08 |
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Donna pose la question : A university is trying to determine what price to charge for football tickets. At a price of 6.oo/ticket it averages 70000 people per game. For every 1.oo increase in price, it loses 10000 people from the average attendance. Each person on average spends 1.5o on concessions. What ticket price should be charged in order to maximize revenue.
price = 6+x, x is the number of increases.
ticket sales = 70000- 10000x
concession revenue 1.5(70000 - 10000x)
I just do not know what to do with the concession part of this equation
(6+x) x (70000 - 10000x) I can understand but not the concession part please help. thx. Penny Nom lui répond. |
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A lidless box with square ends |
2008-04-28 |
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Chris pose la question : A lidless box with square ends is to be made from a thin sheet of metal. Determine the least area of the metal for which the volume of the box is 3.5m^3.
I did this question and my answer is 11.08m^2 is this correct? If no can you show how you got the correct answer. Stephen La Rocque and Harley Weston lui répond. |
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The range of a projectile |
2007-09-18 |
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Claudette pose la question : This is a maximum minimum problem that my textbook didn't even try to give an example of how to do it in the text itself. It just suddenly appears in the exercises.
Problem: The range of a projectile is R = v^2 Sin 2x/g, where v is its initial velocity, g is the acceleration due to gravity and is a constant, and x is the firing angle. Find the angle that maximizes the projectile's range.
The author gives no information other than the formula.
I thought to find the derivative of the formula setting that to zero, but once I had done that, I still had nothing that addressed the author's question.
Any help would be sincerely appreciated.
Claudette Stephen La Rocque lui répond. |
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Optimization - carrying a pipe |
2007-05-05 |
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A student pose la question : A steel pipe is taken to a 9ft wide corridor. At the end of the corridor there is a 90° turn, to a 6ft wide corridor. How long is the longest pipe than can be turned in this corner? Stephen La Rocque lui répond. |
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Maximize the volume of a cone |
2007-04-27 |
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ashley pose la question : hello,
I've been stumped for hours on this problem and can't quite figure it out.
The question is: A tepee is a cone-shaped shelter with no bottom. Suppose you have 200
square feet of canvas (shaped however you like) to make a tepee. Use
calculus to find the height and radius of such a tepee that encloses the
biggest volume.
Can you help?? Stephen La Rocque and Penny Nom lui répond. |
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A cylinder inside a sphere |
2007-04-25 |
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Louise pose la question : i need to find the maximum volume of a cylinder that can fit inside a sphere of diamter 16cm Penny Nom lui répond. |
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A Norman window |
2006-11-30 |
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Joe pose la question : a norman window is a rectangle with a semicircle on top. If a norman window has a perimeter of 28, what must the dimensions be to find the maximum possible area the window can have? Stephen La Rocque lui répond. |
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How much labor should the firm employ? |
2006-10-28 |
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Christy pose la question : A dressmaking firm has a production function of Q=L-L(squared)/800. Q is the number of dresses per week and L is the number of labor hours per week. Additional cost of hiring an extra hour of labor is $20. The fixed selling price is P=$40. How much labor should the firm employ? What is the resulting output and profit? I am having a difficult time with this, HELP! Stephen La Rocque lui répond. |
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The box of maximum volume |
2006-02-01 |
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Elizabeth pose la question : A box factory has a large stack of unused rectangular cardboard sheets with the dimensions of 26 cm length and 20 cm width.
The question was to figure what size squares to remove from each corner to create the box with the largest volume.
I began by using a piece of graph paper and taking squares out. I knew that the formula L X W X H would give me volume. After trial and error of trying different sizes I found that a 4cm X 4cm square was the largest amount you can take out to get the largest volume. My question for you is two parts
First: Why does L X H X W work? And second, is their a formula that one could use, knowing the length and width of a piece of any material to find out what the largest possible volume it can hold is without just trying a bunch of different numbers until you get it. If there is, can you explain how and why it works. Penny Nom lui répond. |
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