cone : Area of the base x height of the cone /3 = pi*r^2*h/3
r : The radius of the base circle
h: The height of the cone
sphere: 4/3*pi*r^3
pyramid: Area of the base of the pyramid x height /3
Volume of pyramid: A*h/3
A: The area of the base of the pyramid
h: The height of the pyramid
The base of the pyramid can have any shape: square, rectangle, triangle, hexagon etc...
Triangular prism: The area of the triangular prism x height of the triangular prism
Volume=A*h
A: area of the triangle
h: height of the prism
V: volume of the prism
Let's say we have a triangle with lengths a,b and c.
U=(a+b+c)/2
A=(U*(U-a)*(U-b)*(U-c))^0.5
V=(U*(U-a)*(U-b)*(U-c))^0.5*h
2007-01-23 22:33:29
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answer #1
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answered by Salih D 1
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This is meant to be a volume, which is real. So perhaps the interval [0, 16] is for the y-axis, since the curve is only defined (real) for the purposes you want when x is on [0, 4], and the peak is over 16 (since the values at x = 2 and 3 are higher than that). This would also define the "bottom" of the solid as being the y=0 line, and the top of it the curve given. For any of these multivariable integrations, you need to consider what happens to a little volume element as you integrate. The volume of integration is a volume of a solid of revolution, so you have a radius which is your 'x' value, but the area has a height which varies from y = 0 to the lesser of the expression or 16. (There are 2 values of 'x' on the interval [0,4] where the expression is greater than 16.) [You could also do this by first integrating the entire volume of the solid of revolution--ignoring the limit on y--and then subtracting off the unwanted volume by looking at revolving the area which extends from y = 16 to the given expression, and from the 'x' crossover point to the second.] You still have to frame this in terms of it being a solid of revolution, but another answerer has talked about using the x value as the radius, etc., and a methodology for finding an answer. I just think that [0,16] must refer to the y values, because it you are looking for a real result. You should get a clarification.
2016-03-29 00:00:47
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answer #2
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answered by Anonymous
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http://www.bbc.co.uk/schools/gcsebitesize/maths/shapeih/areaandvolumerev1.shtml- extracted from here!
Area of a parallelogram and trapezium
The area of a parallelogram is b × h
The area of a trapezium is 1/2 × h × (a + b)
Remember - h is the perpendicular height.
Volumes and surface areas
Prisms
A prism is a shape which has a uniform cross section.
The volume of a prism is the area of cross section x length.
The formula to remember is V = A × L
The volume of a cylinder is therefore r2 x length.
The surface area of a prism is the area of both ends, plus the sum of the areas of the sides.
The surface area of a cylinder is the area of both ends (2r2) plus the curved surface area (2rl)
Surface area of a cylinder:
= 2r2 + 2rl
= 2r(r + l)
Pyramids and cones
A pyramid is any shape that goes up to a point at the top. The base can be any shape, but when the base is a circle, it's called a cone.
The volume of a pyramid is: × base area × perpendicular height.
Therefore, the volume of a cone is: r2h.
The curved surface area of a cone is: rl (where l is the slant height).
Spheres
The volume of a sphere is: r3
The surface area of a sphere is: 4r2
Length, area and volume
How do we check that: r3 is the formula for a volume of a shape or that 2r(r + l) represents a surface area? We use dimensional analysis.
In both these formulae the letters r (radius) and l (slant height) represent lengths. The numbers (including , which is just 3.141....) are irrelevant, so we ignore them!
Here are the rules to remember for working out whether a formula is for a length, area or volume:
A formula with lengths occuring on their own is for a length.
A formula with lengths multiplied in pairs (eg r 2) is for an area.
A formula with lengths cubed (eg r3) will be for a volume.
Let's look at the formula for the volume of a sphere.
r3
If we remove all the numbers, the formula r3 becomes r3
r3 is length × length × length = volume
So r3 represents a volume.
Now let's look at 2r(r + l).
By removing all the numbers from 2r(r + l) we get r2 + rl
As r2 + rl includes a length squared, the formula represents an area. The formula is for the area of a cylinder.
Remember:
After all the numbers have been removed in a formula, you may be left with a combination of length, area and volumes. Here are the rules for simplifying these:
length length = length
area area = area
volume volume = volume
length × length = area
length × area = volume
volume/area = length
volume/length = area
Everything else is impossible (eg length + area, area × area).
2007-01-23 23:12:48
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answer #3
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answered by Anonymous
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Cylinder, triangular prism, square prism and anything else where the sides go straight up:
volume = base x height
Cone with any shape base, pyramid with any shaped base, any figure where lines go up from base to a single point:
volume = 1/3 x base x height
Sphere:
volume = 4/3 * Pi * radius cubed
2007-01-23 22:35:29
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answer #4
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answered by Gnomon 6
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Volume of the Cone = (1/3) pi r^2 h, pi = 3.142
Volume of the Sphere = (4/3) pi r^3, pi = 3.142
Volume of the Pyramid = (1/3) ( area of the base)* h, pi = 3.142
Volume of the Triangular Prism
= ( area of the trianglular base) h, pi = 3.142
Volume of the Cylinder= pi r^2 h, pi = 3.142
Volume of the Rectagular Parallelopiped
= length * breadth * height
Volume of the Cube = ( length)^3
2007-01-23 23:50:03
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answer #5
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answered by Anonymous
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Volume Formula for a sphere
V = 4/3 π r³
Volume formula for a clinder
V = π r² h
Volume formula for a cone
V = 1/3 π r² h
Volume formula for a Prism
V = B h
Volume formula a Pyramid
V = 1/3 B h
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2007-01-24 00:02:04
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answer #6
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answered by SAMUEL D 7
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For a cube it is Volume= Length x Width x Height
2007-01-23 22:49:06
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answer #7
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answered by Anonymous
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That's easily looked up on google
I'll give you the one I know from memory:
Sphere is (4/3)(pi)(r^3)
2007-01-23 22:32:21
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answer #8
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answered by Mathematica 7
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for a cube it is l*b*h
2007-01-23 23:08:03
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answer #9
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answered by Anonymous
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