use theorem 4.2.1 to determine which of the following are subspace of R^3 . Theorem 4.2.1 is (a)u+v=w
(b) ku=w
this are question i need help with
(a) All vectors of the form (a,0,0)
(b) All vectors of the form (a,1,1)

Question

use theorem 4.2.1 to determine which of the following are subspace of R^3    . Theorem 4.2.1 is (a)u+v=w
(b) ku=w
this are question i need help with
(a) All vectors of the form (a,0,0)
(b) All vectors of the form (a,1,1)

anonymous · Answer

What is theorem 4.2.1?
a is a subspace, b is not.

anonymous · Answer

show me example

anonymous · Answer

a is closed under vect add and scalar multi, but b is not closed.

anonymous · Answer

can you  show me how (a) is under vector add and scalar multi, and be is not

anonymous · Answer

add two vectors or multiply them by 2 - then a vector of type a is still type a, but a vector of type b is not of type b anymore.