20 a R2 is a twodimensional subspace of R3 b The number of v

20. a. R2 is a two-dimensional subspace of R3. b. The number of variables in the equation Ax 0 equals the dimension of Nul A c. A vector space is infinite-dimensional if it is spanned by an infinite set. d. If dim V n and if S spans V, then S is a basis of V e. The only three-dimensional subspace of R3 is R3 itself.

Solution

c is the correct answer