maths things to remember

n(A)

number of elements in set A

A ⊂ B

A is a proper subset of B

all elements in set A are in set B, but not all elements in set B are in set A

∅

empty set (the set with no elements)

a^-1

1/a

a^1/2

√a

sin graph

cos graph

tan graph

area of segment

= area of sector-area of triangle

angle at the centre

the angle at the centre is twice the angle at the circumference

angles on the same arc

angles on the same arc are equal

angles in a semicircle

angles at the circumference standing on a diameter are equal to 90

cyclic quadrilateral

opposite angles of cyclic quadrilateral add up to 180

tangent to a circle

tangent to a circle always perpendicular to radius at point of contact

two tangents drawn from same point are equal in length

alternate segment

angle between a tangent and a chord is equal to any angle made by that chord in the alternate segment

direct proportion

y∝x

y=kx

inverse proportion

y∝1/x

y=k/x

domain

what is put in to a function

range

what you get out of a function

frequency density =

Frequency/class width

intersecting chord theorems

f(2x)

horizontal shrink by 1/2

2f(x)

vertical stretch by 2

y=-f(x)

reflection in x axis

y=f(-x)

reflection in y axis

f(x)+b

change in y by b

f(x+a)

change in x by -a