Maths

• Volume of prism

  area of cross section x length
• Volume of cylinder

  pie x r squared x h
• Volume of pyramid

  1/3 x area of the base x height
• Exact trig values

  
• 4 ways of proving congruence

  SSS,SAS,ASA,RHS
• Corresponding angles are equal F
• Alternate angles are equal Z
• Co-Interior angles add to 180 C
• Opposite angles are equal X
• Exterior angle of a triangle is equal to the sum of the opposite interior angles
• circumference = pi x d
• area of a circle = pie x r^2
• area of trapezium = 1/2 (a+B)distance between them
• speed= distance/time
• density= mass/volume
• pressure= force/area
• equation of a circle

  x^2 + y^2 = r^2
• finding radius from centre and point on circumference

  r^2 = (x-a)^2 + (y-b)^2 where (a,b)=centre and (x,y) is a point on the circumfrence
• area of triangle = 1/2 x a x b x sinC
• when line is in form (x+a)^2 + b , the turning point = (-a,b)
• Sum of exterior angles = 360
• sum of interior angles = n-2(180)
• frequency density = frequency / class width
• new = original x (1+n)^t
• lsf= x, asf = x^2, vsf = x^3
• pie = ratio of circumference : diameter
• A kite has 2 equal length sides and no parallel sides
• Parellelograms have 2 pairs of parallel sides
• Trapeziums have 1 pair of parallel sides
• Rhombus sides are all the same length and opposite angles are equal
• Iscosceles trapeziums have 1 pair of equal length sides
• 1st five triangular numbers and how to find the next term

  1, 3, 6, 10, 15

  Add previous difference + 1
• Fibonacci sequence
• Fibonacci sequence: A sequence of numbers in which each number is the sum of the two preceding numbers.
• Quadratic sequence method


  1)Find second difference

  2)Halve second difference to find a

  3)Sequence-an^2 to form linear sequence

  4)Find nth term of linear sequence
• In a geometric sequence terms are multiplied by the same amount each time
• If b^2-4ac is equal to 0, the line has one root
• If b^2-4ac>0, the line has 2 roots
• If b^2-4ac<0, the line has no roots
• a^n x a^m = a^n+M