Linear Combination
A linear combination of the vectors { v 1 , , v m } of vectors in V a 1 v 1 + + a m v m where a 1 , , a m F
Span
The set of all linear combinations of the vectors { v 1 , , v m } V called the span of { v 1 , , v m } and we define the notation: span ( { v 1 , . . . , v m } ) := { a 1 v 1 + + a m v m : a 1 , . . . , a m F } we define span ( ) := { 0 }
Linearly Independent
A set of vectors { v 1 , , v m } V is said to be linearly independent if the only solution to i = 1 m a i v i = 0 is i { 1 , . . . , m } , a i = 0 . We define to be linearly independent.
Linearly Independent iff Unique Representation
{ v 1 , , v m } is linearly independent iff each vector in the set { v 1 , , v m } has only one representation as a linear combination of { v 1 , , v m }
Linearly Dependent
{ v 1 , , v m } V is said to be linearly dependent if it is not linearly independent
Linearly Depedent iff Zero has a Non-Trivial Representation
{ v 1 , , v m } V is linearly dependent iff there exists a 1 , , a m F and i [ 1 , m ] where a i 0 such that i = 1 m a i v i = 0