SOLUTION: Please , I need help with this one.
Evaluate the indicated minor and cofactor for the determinant
3 -2 3
1 3 0
6 -2 3 M23, C23
How
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-> SOLUTION: Please , I need help with this one.
Evaluate the indicated minor and cofactor for the determinant
3 -2 3
1 3 0
6 -2 3 M23, C23
How
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Question 47668This question is from textbook College Algebra
: Please , I need help with this one.
Evaluate the indicated minor and cofactor for the determinant
3 -2 3
1 3 0
6 -2 3 M23, C23
How will I know which row and column to delete? What does 23 signifies? This question is from textbook College Algebra
You can put this solution on YOUR website! number the determinant as follows
R1=ROW1,R2=ROW2...ETC....C1=COLUMN1 ETC...
............C1......C2......C3
R1..........3..... -2...... 3
R2..........1...... 3...... 0
R3..........6..... -2...... 3
WE CALL THE ELEMENT OR NUMBER AT THE INTERSECTION OF R1 AND C1 AS...E11 SAY.THIS IS 3
SIMILARLY...E32=ELEMENT IN R3 AND C2 = -2...ETC....
NOW M23 MEANS MINOR OF E23..THAT IS ELEMENT IN R2 AND C3 = 0...
FOR THIS PURPOSE YOU SHOULD REMOVE THR ROW AND COLUMN CONTAING E23...THAT IS REMOVE R2 AND C3 FULL..WE GET
...........C1.......C2..........C3 REMOVED
R1.........3.......-2
................................R2 REMOVED
R3.........6.......-2
SO WE GET A 2 BY 2 DETERMINANT AS MINOR OF A 3 BY 3 DETERMINANT.
NOW C23 MEANS COFACTOR OF E23..IT IS THE ABOVE DETEMINANT THAT IS M23 MULTIPLIED BY (-1)^(2+3)=(-1)^5=-1
SO C23=-1M23
SIMILARLY
C11=(-1)^(1+1)M11=M11
C12=(-1)^(1+2)M13=-M12...ETC....
