maths formulas

• frequency density = frequency / group width
• surface area of a cylinder = (2 x pi x r x h) + (2 x pi x r^2)
• volume of a sphere = (4/3 x pi x r^3)
• volume of a pyramid = (1/3 x base area x slant height)
• volume of a rectangular prism = l x w x h
• volume of a cube = s^3
• area of a sphere = (4 x pi x r^2)
• arc length = A/360 x (2 x pi x r)
• area of a sector = A/360 x (pi x r^2
• volume of prism - B (base area) x H (height)
• interior angles in a polygon = (no. of sides - 2) x 180
• exterior angles = 360 / number of sides
• no.of sides x exterior angles = 360
• int angles + ext angles = 180
• all ext angles add up to 180
• simple interest = P (initial balance) x r(interest rate) x time (number of yeras)
• sine rule

  sinA/a = sinB/b = sinC/c
• cosine rule

  a2 = b2 + c2 x 2bc x CosA
• cosine rule (for angles)

  CosA = b2 + c2 - a2/ 2bc
• area of non-right angle triangle

  1/2abSinC
• gradient with coordinates


  change in Y/ change in X
• midpoint of a line


  (x1 + x2/2), (y1+y2 / 2)
• volume of a cone


  1/3 x pi x r2 x h
• surface area of a cone

  pi x radius x slanted height
• total surface area of a solid cone


  (pi x radius x slanted height) + (pi x r2)