Scalar and Matrix Multiplication Answers

11 verified answers2 views
3

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Answer:

7

5

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Answer:

-8

6

What is the correct formula for calculating a 3 x 3 determinant?

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A
abc + def + ghi - adg - beh - cfi
B
adg + beh + cfh - abc - beh - cfi
C
aei + bfg + cdh - gec - hfa - idb
8

Which of the following statements are true?

A
If any row of a square matrix is zero, its determinant is zero.
B
If all numbers in a matrix are equal, its determinant is zero.
C
The determinant of any identity matrix is zero.
D
The determinant of a matrix with all positive numbers is always positive.
E
The determinant of any zero matrix is zero.
10

Consider the matrix:What is its determinant? Does the determinant depend on the variables? Make a conjecture.

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Answer:

The determinant of the matrix is 8. This is calculated by multiplying the diagonal elements (1 * 2 * 4 = 8) because the matrix is upper triangular. The determinant does not depend on the variables x, y, and z. I conjecture that when all elements below the main diagonal are zero, the determinant is always the product of the main diagonal elements.

11

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Answer:

162

12

Which of the following did your answer include?

A
The determinant is 8.
B
The determinant does not depend on the variables in the matrix.
C
When there are zeroes below the main diagonal, the determinant is the product of the diagonal.

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