Definition 1
A
basis of a vector space
is a set of vectors
such that
-
.
-
is linearly independent.
The second condition ensures that all bases of
will have the same size. In
fact, the dimension of a vector space
is defined as the number of elements
required in a basis for
. (Could easily be in infinite.)
-
with
the “standard basis” for
Note that this easily extends to
.
-
with any set of
linearly independent vectors
-
(Note that the dimension of
is
)
-
(Fourier series, infinite dimensional)