Friday, February 5, 2010

Math: Geometry

Area:
Triangle: A=1/2 (base)(height)
Square/rectangle/parallelogram: A=(base)(height)
Trapezoid: A=(Height/2)(base 1 + base 2)
Circle: A=(pi)(radius)^2
Eclipse: A=(pi)(radius 1)(radius 2)

Volume:
Cube/Rectangular Prism: V=(base)(height)(width)
Cylinder: V=(pi)(radius)^2(height)
Cone: V=(1/3)(pi)(radius)^2(height)
Pyramid: V=(1/3)(base)(height)
Sphere: V=(4/3)(Radius)^3
Ellipsoid: V=(4/3)(radius 1)(radius 2)(radius 3)

Circles:
Circumference: C=(pi)(diameter)
Length of Arc: L=(radius)(theta) ... If theta is in radians.
Length of Arc: L=(radius)(pi/180)(theta) ... If theat is in degrees.
Area of Circle piece: A=(theta/360)(pi)(radius)^2 ... If theta is in degrees.
Area of Circle piece: A=(theta/2pi)(pi)(radius)^2