Some useful mathematical formulae

2D	3D
Square, side a                 Area = a2  = 1/2d2, where d is the diagonal Diagonal, d = a√2 Perimeter, p = 4a Rectangle Area, a = lb (l=length, b=breadth) Perimeter, p=2(l+b) Diagonal, d=√(l2+b2) Circle Area, a = πr2 Circumference = 2∏r Sector of a circle Arc length = (2πrα/360), α is the angle Area = πr2α/360	Cube Volume, v= a3=(d/√3)3 Faces =6 Vertices=8 Edge=12 Total Surface area = 6a2 Lateral Surface area=4a2 Diagonal, d=a√3  Rectangular Cuboid Volume, v=lbh Total Surface Area = 2(lb+bh+lh) Lateral Surface area = 2h(l+b) Diagonal, d=√(l2+b2+h2) Sphere V=4/3πr3 Total Surface Area = 4πr2 Hemisphere Volume, v= 2/3πr3 Curved Surface area = 2πr2 Total Surface area = 2πr2 + πr2 = 3πr2