The equation
is solved using
You can choose r from n possibilities in
possible ways.
You can line up r from n possibilities in
different ways
Binomial Theorem :
For any triangle ∆ABC ,
The straight line passing through
has gradient
and equation
The distance between two points, is
A straight line
passing though points A and B is given by
The angle between two vectors
is given by
The angle between two lines
and
is given by
To change
to a straight line equation, take logs
and
