Determinants and Singular Matrices

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Determinants and Singular Matrices

• WJEC Past Paper Question
• P5 June 2004

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Expanding about ROW 1
3
A SINGULAR MATRIX has a determinant of ZERO
To show that A is non singular FOR ALL VALUES OF
X we need to show that the minimum value of the
determinant is GREATER THAN ZERO
Completing the square
The minimum value of the determinant is 3
And so we can conclude that the matrix is NON
SINGULAR