In: Advanced Math
be two linear transformation with range (T1) = range(T2) .
Let { v1 , v2 ,...,vm } be a basis of range(T1) .
There exist { u1 , u2 , ... ,um} and{ w1 , w2 , ... ,wm} such that
T1( u1 ) = v1 , T2( w1) = v1
T1( u2) = v2 , T2 ( w2 ) = v2
..................
Tm( um ) = vm , Tm( wm ) = vm .
Since { v1 , v2 ,...,vm } be a basis of range(T1) so { u1 , u2 , ... ,um} and { w1 , w2 , ... ,wm} are also linearly independent because image of linearly dependent set is linearly dependent .
Now since { u1 , u2 , ... ,um} and { w1 , w2 , ... ,wm} are linearly independent so they can be extend to a basis of .
Let { u1 , u2 , ... ,um , um+1 ,..., un } and { w1 , w2 , ... ,wm , wm+1 , ...,wn } are basis of .
Define , is defined by ,
U(ui ) = wi for all i = 1,2 ,...,n
Then