Geometry
Triangles
A=1/2bh
A=1/2cbsin(A)
A=(sqrt(3)/4)*a^2
A=sqrt(s(s-a)(s-b)s(-c))
where s=(a+b+c)/2
Parallelogram
A=absin(A)
A=bh
Cosine theorem
a^2=b^2+c^2-2bc*cos(A)
Rectangular: sin 90=1 therefore
A=ab
Square: a=b therefore
A=a^2
Volume
Circle
A=piR^2
Rectangular prism
Sphere
Cylinder
Cone
Pyramid
V=abc
V=(4/3) pi r^3
V=(1/3)bh=1/3 pi r^2 h
V=bh=pi r^2 h
V=(1/3) bh
irregular prism
cube
V=a^3
V=bh
Area
Trapezoid
h/2(b1+b2)
Surface area
Sphere
4pi r^2
Cube
6a^2
Right circular cylinder
2pi r^2 +2pi r h
Rectangular prism
2lw + 2lh + 2wh
where
l is the length
w is the width
h is the height
Right circular conus
pi r^2 + pi r l
Right square pyramid
a^2+2al