30 60 90 triangle - Side opposite 30 degree angle
x (smallest side)
30 60 90 triangle - Side opposite 60 degree angle
x√3 (medium side)
30 60 90 triangle - Hypotenuse
2x (largest side)
law of sines
a/sin A = b/sin B = c/sin C
law of cosines
c = √(a² + b² - 2ab cos C
law of cosines solved for other things
a² = b² + c² - 2bc cosA
b² = a² + c² - 2ac cosB
c² = a² + b² - 2ab cos C
combination equation
n = number of objects
r = objects selected each time
n!/(r!(n-r)!