We use the Pythagoras Theorem to derive a formula for finding the distance
between two points in 2- and 3- dimensional space.
Let
P = (x 1, y 1)
Q = (x 2, y 2)
be two points on the Cartesian plane
Then
from the Pythagoras Theorem we find that the distance between P and Q is
PQ=((x2-x1)^2+(y2-y1)^2)^0.5
In a
similar way
it can
be proved that if
P = (x 1, y 1, z1) and
Q = (x 2, y 2, z2) are two
points in the 3-dimensional space,
the
distance between P and Q is
PQ=((x2-x1)^2+(y2-y1)^2+(z2-z1)^2)^0.5
