Saturday, February 2, 2008

Are you okay with matrices?

Hello, we have learnt matrices together in class and now I hope you will take the following quiz on matrices to check how well you have learnt the topic.


1) When adding matrices of the same orders/dimensions, will the answer have the order/dimension of the matrices?

2) When multiplying, do matrices need to be of the same orders/dimensions?

3) Can you multiply a matrix by something other than another matrix?

4) When adding matrices, do you add different positions together?


If any of your answers is a "no", please write to explain why you say so.


Post your answers to these 4 questions by 5 Feb.

33 comments:

Anonymous said...

2. NO. the number of columns in the first matrix have to be the same as the number of rows in the second matrix, thats the only requirement.


4. NO. the top left of matrix1 adds with the top left of matrix2. Same goes to the other sides. We cannot randomly add them up.

Anonymous said...

1. Yes

2. No, it requires the number of columns and rows to be the same for first and second matrices

3. Yes, scalar multiplication.

4. Add corresponding position only.

Anonymous said...

2) no . the number of columns in matrix (1) must be equal to the number of rows in matrix (2).

4)the matrices involved must be of same order . which means that
(a b) + (w x) = (a+w b+x)
(c d) (y z) (c+y d+z)

OLL said...

Clarence - good answer to no.2; however for no.4, I can say I understand what you are trying to say although you can be more specific. Look at Chun Lik's (kikilala) response to no.4

OLL said...

Shawn - good, clear explanation, esply for no.4 where you used a specific example to illustrate what you said.

Anonymous said...

1 yes
2 no , the number of first matrix's column must be as same as the number of second matrix's row .
3 yes
4 adding them to the same position

Anonymous said...

2) no, number of columns in the 1st matrix must be the same as number of rows in the 2nd matrix.

4) no, the most left hand side in the 1st matrix must add with the most left hand side in the 2nd matrix.

Anonymous said...

1.yes.

2.no.the number of numbers in the row of the 1st matrix must be the same as the number of numbers in the coloum of 2nd matrix.

3.yes.

4.no.we add the numbers in the matrix according to there respective position.

Anonymous said...

1) Yes
2) No,as long as the number of columns in matrix 1 is equal to the number of rows in matrix 2
3) Yes
4) No,we only can add the numbers in the same positions.

Anonymous said...

1) Yes

2) No, but the no. of columns in the 1st matrice has to be the same no. of rows in the 2nd matrice if not, it would be impossible to multiply.

3) Yes

4) No, you only add numbers according to their position in ach matrice. For example, for a 1 x 2 matrice, (6 7) + (4 9) = (10 16).
According to each number's position in the matrice.

Anonymous said...

1.Yes
2.Nope..the no. of column in 1st matrix must be the same as the no. of rows in the 2nd matrices.
3.Yup
4.No..We should only add matrices which are in the same position..

OLL said...

Can you pls identify yourself, fishball?

Anonymous said...

1. Yes

2. No. it only requires the no. of numbers in the row of the first matrix be the same as the no. of numbers in the column of the second matrix to be the same.

3. Yes. By having another number/constant in front of the matrix (Scalar Multiplication).

4. No. it only require us to add them up using the same position of the two different matrix.

Anonymous said...

1) Yes.
2) no. no. of rows and columns of the matrix must be the same or else it cannot be multiplied
3) yes
4)no. you are require to add them in the same position.

Anonymous said...

1)Yes
2)No...It only require the no. of columns in the first matrix to be equal to the no. of row in the second matrix
3)Yes by using scalar
4)No...We only add them up when they are in the same position

Anonymous said...

1)yes
2)no. the number of columns in matrix 1 must be equal to the number of rows in matrix 2
3)yes
4)no. for matrix addition, the matrices involved must be of the same order

Anonymous said...

1. yes
2. no. the numbers of columns in matrix 1 must be equal to the number of rows in matrix 2
3. yes
4. no. for matrix addition, the matrices involved must be of the same order

Anonymous said...

1. Yes
2. No, only numbers of columns in the first matrix to be equal to numbers of row in the second matrix.
3. Yes
4. No, only add when it is in the same position.

Anonymous said...

1) yes
2) no, thenumber of columns of the first matrix jus nid to be the same number of column as the second matrix
3)yes
4)the elements in a matrix represents something and if you add different positions of the matrices, the result will be wrong.

Anonymous said...

1. Yes =)

2. No. =(
First matrix and second matrix have to have the same number of columns and rows.

3. Yes =)

4. No. =(
Add the same position number to the other same position number.

Anonymous said...

Looks like everyone understands the basics of matrices quite well. Thank you for your posts.

Anonymous said...

2. No. only the number of columns in the first matrix and the number of rows in the second matrix must be the same.

4. No. only add the matrices up in their respective positions.

Anonymous said...

1) Yes.
2) No, it needs to be in the same columns and rows.
3) Yes.
4) No, it must be in the same order and position.

Anonymous said...

1. Yes.
2. no. As the colum of the first matrix need to be the same as the row of the second matrix.
3. yes. Saclar multiplication
4. no. it need to be in the same positon and order.

Anonymous said...

1)Yes.
2)No-When multiplying, it is required that the first matrix's column must be as same as the number of the second matrix's
3)Yes.
4)No-add to each corresponding position only

P.S sorry late.....

Anonymous said...

2. No, the number of column in the first matrix must be same to the number of row in the second matrix only.

4. No, matrices can only be added in the same position only.

Anonymous said...

1)yes.
2)no ,the number of rows in the first matrix must be the same as the numbers of rows in the second matrix.
3)yes.
4)no, we must add them according to their positions.

Anonymous said...

2)no. it can be in any order/dimensions but the number of columns in the first matrix must corresponds with the number of rows in the second matrix.

4)no. add numbers in the same postion together only.

Anonymous said...

2) no, the number of columns in the 1st matrix must be the same as the number of rows in the 2nd matrix.
4) no, we add the matrix according to the same position.

Anonymous said...

1. Yes
2.No (*1 #2) (*a ^b )
^3 _4 #c _d
3.Yes
4.No, different order can't add together

Anonymous said...

2) no, number of columns in the 1st matrix has to be equal to number of rows in the 2nd matrix.

4) no, you are required to add them in the same position.

Anonymous said...

2)No.The number of columns in the first matrix have to be the same as the number of rows in the second matrix.

4)No.We should add them in the same position.
eg: (a b) + (c d)=(a+c b+d)

Anonymous said...

2. No. no. of columns in the first matrix should be the same as no. of row in second matrix.

4.No.we should add correspondingly.
eg:(x y)+(m n)=(x+m y+n)