(4-17-2012)Aim: How do we find the volume of cones?

(4-17-2012)Aim: How do we find the volume of cones?

Cone 
The volume of a cone is shown by the formula v=1/3πr²h

http://3dshapes.org/images/stories/3dshapesclipart/thumbs-medium/cone1.pngExample:
What is the volume of a cone with a radius of 3 and a height of 9?
Leave it in the terms of π.
Answer:
v=1/3πr²h
v=1/3π3²(9)
=π9(9)/3
=81π/3
=27π units^3

Try it yourself!
What is the volume of a cone with a radius of 2 and a height of 7?

(4-18-2012)Aim: How do you find the surface area and volume of a sphere?

(4-18-2012)Aim: How do you find the surface area and volume of a sphere?

Spheres
       A sphere is the set of all points in a space equidistant from a given point called the center.

Surface area and volume formula for a sphere:

http://0.tqn.com/d/math/1/0/I/F/spherer.gif
Examples:
Surface Area
What is the surface area of a sphere with radius 5?
 leave it in the terms of π.
SA: 4πr²
4π5²
4π25
100πunits²

Volume:
What is the volume of a sphere with a radius of 8ft?
4πr^3 /3
4π8^3/3
4π512/3
2048π/3
=682.67πft^3 or 2143.6 ft ^3

Try it yourself!
Find the volume and surface area of 7in?