# Ex 4.4, 5 - Chapter 4 Class 12 Determinants

Last updated at Jan. 22, 2020 by Teachoo

Last updated at Jan. 22, 2020 by Teachoo

Transcript

Ex 4.4, 5 If ∆ = |■8(a11&a12&a13@a21&a22&a23@a31&a32&a33)| and Aij is Cofactor of aij then value of ∆ is given by (A) a11 A31 + a12 A32 + a13 A33 (B) a11 A11 + a12 A21 + a13 A31 (C) a21 A11 + a22 A1 2 + a23 A13 (D) a11 A11 + a21 A21 + a31 A31 If ∆ = |■8(a11&a12&a13@a21&a22&a23@a31&a32&a33)| ∆ = Sum of products of elements of row (or column) with their corresponding cofactors ∆ = a11 A11 + a21 A21 + a31 A31 So, option D is correct

Chapter 4 Class 12 Determinants

Concept wise

- Finding determinant of a 2x2 matrix
- Evalute determinant of a 3x3 matrix
- Area of triangle
- Equation of line using determinant
- Finding Minors and cofactors
- Evaluating determinant using minor and co-factor
- Find adjoint of a matrix
- Finding Inverse of a matrix
- Inverse of two matrices and verifying properties
- Finding inverse when Equation of matrice given
- Checking consistency of equations
- Find solution of equations- Equations given
- Find solution of equations- Statement given
- Verifying properties of a determinant
- Two rows or columns same
- Whole row/column zero
- Whole row/column one
- Making whole row/column one and simplifying
- Proving Determinant 1 = Determinant 2
- Solving by simplifying det.
- Using Property 5 (Determinant as sum of two or more determinants)

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.