Area of a circle:
πr^2
Circumference of a circle:
πd or 2πr
General circle equations:
(x-a)^2 + (y-b)^2 = r^2
x^2 + y^2 +2gx + 2fy +c = 0
Areas of a triangle:
1/2 * bh
1/2 * absinC
Area of a trapezium:
(a+b)/2 * h
Area of a kite/rhombus:
(pq)/2
p and q are the diagonals
Area of a parallelogram:
bh
Volume of a sphere:
4/3 πr^3
Surface area of a sphere:
4πr^2
Volume of a cuboid:
a * b * h
Surface area of a cuboid:
2(ab + bh + ah)
Volume of a square based pyramid:
(lwh)/3
Surface area of a square based pyramid:
lw + l((w/2)^2 + h^2)^1/2 + w((l/2)^2 + h^2)^1/2
Volume of a cylinder:
πr^2h
Surface area of a cylinder:
2πrh + 2πr^2
Volume of a prism:
A(base) * l
l = length
Surface area of a prism:
2 * A(base) + p(base) * h
p = perimeter
Volume of a cone:
πr^2 * h/3
Surface area of a cone:
πr(r + (h^2 + r^2)^1/2)
radius equation for circle:
(g^2 + f^2 -c)^1/2
