I want to do a set of high level questions, urgently, I can still add points

I can only give you a rough rundown of your question :

1。Such a mapping doesn't seem to exist.

2。The difference is that the elements of the number field are multiplicative and interchangeable, there are multiplicative unit elements, and each non-zero element has an inverse element. Also, I haven't heard much of the number ring. A ring is a ring.

3。For example, all forms such as a+b times the root number 2, where a and b are rational numbers. Replace 2 with 3 to get another number field.

4。The intersection of two rings must be rings, but I don't know what you mean by number rings.

5。Swapping two rows or columns, multiplying one row or column by a constant changes the value of the determinant.

6。The constant term is 0.

7。There are two commonly used ones that I know: Gaussian elimination and Clemm's rule.

8。As long as the determinant of the coefficient matrix is not 0, it can be used.

9。The Gaussian elimination method is used to form a standard form, and if the system of equations is full of rank, there is only one solution; If the rank is not satisfied and compatible, there are infinite solutions; If you are not in rank and incompatible, there is no solution. The kind of situation you're talking about can't happen.

10。By definition, it is the order of the sub-square with the largest order of the determinant that is not 0.

11。No.

12。The number of columns in the previous matrix is equal to the number of rows in the latter matrix.

13。You still have to flip through the book by yourself in this relational formula, it's not easy to type.

14。The rank of and is independent of the rank of two matrices; The rank of the product does not exceed the rank of either of the two matrices.

15。Use the elementary transformation to turn the matrix into an upper triangle and see how many diagonal elements are not 0

16。When a known matrix is placed side by side with a unit matrix, only the elementary row transformation is made, and when the left matrix becomes a unit matrix, the right unit matrix becomes the required inverse matrix.

17。When each tile is seen as an element, it is necessary to be able to add and multiply.

18。Generally not suitable.

You can do the proof questions yourself, I can't type it out for you here.

Only the last one is true, and the first three are all wrong.

Explain the noun and flip through the book yourself, I'm tired of typing.

It looks like a certain floor copied the content of a certain floor. Bad.

See Advanced Algebra and Linear Algebra textbooks.

Landlord, you wait, when I review the high math, I will reply to you immediately, there are three more months, just wait three months.

This ** is a high school question, fainting to death,

I know a tutor who needs to contact me if you need help!

I know a lot of tutors, if you want help, don't contact me, I'm making up classes, busy.

I learned it in my freshman year, and now I forget it.

Hehe! It's so hard! I didn't do anything like this when I was in high school, did I?

If it is sent to my mailbox, I can do it, but it is too difficult to write here, and I will not write it here anymore.

This is your exam paper...

I'm most afraid of math and I'm most afraid of typing.

Can't help.

It's also troublesome to write it out!!

Ask your classmates or teachers to do it easily!

This high school is still a junior high school question.

Motion sickness, do you think I graduated from Tsinghua University.

Dizzy, I even thought it was someone else's.

You probably copied the entire test paper and pulled it out.

Answer: Since the part after b in the formula of the penultimate equal sign is obtained by the second determinant of the previous step in the last column, and the position of the only non-zero element (n-1)a in this last column is in the n-1 column of the first row, then b should be multiplied by the (1+n-1) power of -1, that is, the nth power of -1.

This is the line offensive in the determinant calculation method.

To calculate, you must multiply a negative one row plus a column power.

This is Formula A for the formula method in the first column

Homework help welcomes your baby, and those answering software, I'm sorry for my poor education to help you.

I forgot how to calculate the matrix, which is the backward extrapolation method. If a -ab=e is true, then e must be.