formulas

• cosine rule


  a² = b² + c² - 2bccos(A)
• sine rule


  a / sinA = b / sinB = c / sinC
• c² = a² + b²
• trigonometry

  tan (θ) = opposite/adjacent
• trigonometry

  sin (θ) = opposite/hypotenuse
• trigonometry

  cos (θ) = adjacent/hypotenuse
• area of a triangle

  1/2 x b x h
• area of a right-angled triangle

  1/2 x a x b sinC
• area of a trapezium

  1/2 (a+b) h
• rectangle

  length x width
• parallelogram

  base x height
• circumference of a circle

  π x diameter
• circumference of a circle

  2 x π x radius
• area of a circle

  πr2
• quadratic formula

  (-b±√(b²-4ac))/(2a) 
• volume of a prism

  area of cross section x length
• cylinder

  πr2 x h
• pyramid

  1/3 x area of base x height
• speed formula

  speed = distance / time
• density formula

  density = mass / volume
• pressure formula

  pressure = force / area
• interior angle of a polygon 


  (n - 2) x 180
• exterior angle

  360 / number of sides
• exact trigonometry

  sin0 = 0
• exact trigonometry

  sin30 = 1/2
• exact trigonometry

  sin45 = 1 / √2
• exact trigonometry

  sin60 = √3 / 2
• exact trigonometry

  sin90 = 1
• exact trigonometry

  cos0 = 1
• exact trigonometry

  cos0 = √3 / 2
• exact trigonometry

  cos45 = 1 / √2
• exact trigonometry

  cos60 = 1/2
• exact trigonometry

  cos90 = 0
• exact trigonometry

  tan0 = 0
• exact trigonometry

  tan30 = 1 / √3
• exact trigonometry

  tan45 = 1
• exactly trigonometry

  tan60 = √3
• exact trigonometry

  tan90 = undefined