5. The necessary and sufficient condition for a group of n-dimensional vectors to be linearly independent is (). There exists a group of numbers which are not all zero, such that; 5. The necessary and sufficient conditions for the linear independence of n-dimensional vector group are as follows: (1) there exists a group of numbers which are not all zero, so that any two vectors in; (2) there exists a vector in; (3) it cannot be expressed linearly by the other vectors; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4)

5. The necessary and sufficient condition for a group of n-dimensional vectors to be linearly independent is (). There exists a group of numbers which are not all zero, such that; 5. The necessary and sufficient conditions for the linear independence of n-dimensional vector group are as follows: (1) there exists a group of numbers which are not all zero, so that any two vectors in; (2) there exists a vector in; (3) it cannot be expressed linearly by the other vectors; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4) there is a vector in; (4)

D correct

Why is the result of multiplying n-dimensional row vector by n-dimensional column vector in linear algebra a number?
Why not a row column matrix?

A matrix is a number table, but the operation of the matrix gives the number table various practical meanings. For example, it represents the coefficients of the equations, expresses the linear relationship between vectors, and so on. Since it is a number table in essence, they multiply and add each other to get a number, then a 1 * 1 matrix is a number of course

In linear algebra, do you use an arrow on an n-dimensional vector
It's the bold part of the book

Plus, as long as it's a vector, you have to add, including the zero vector
The handwritten one must be added, and the black one on the book is printed, so it is not added
After all, I'm not a book

In R (n-dimensional space), can all the vectors which satisfy the following conditions form the subspace of R (n-dimensional space)
（1）x1+x2+.xn=0（2）x1+x2+.+xn=1

The first one is OK, the second one is not
The reasons are:
The first one is closed by addition (and multiplication), but the second one is not