CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Using Cofactors of elements of second row, evaluate.

Open in App
Solution

The given determinant is.

We have:

M21 =

∴A21 = cofactor of a21 = (−1)2+1 M21 = 7

M22 =

∴A22 = cofactor of a22 = (−1)2+2 M22 = 7

M23 =

∴A23 = cofactor of a23 = (−1)2+3 M23 = −7

We know that Δ is equal to the sum of the product of the elements of the second row with their corresponding cofactors.

∴Δ = a21A21 + a22A22 + a23A23 = 2(7) + 0(7) + 1(−7) = 14 − 7 = 7


flag
Suggest Corrections
thumbs-up
21
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Evaluation of Determinants
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon