determinants-of-matrices

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Determinant of a 2×2 matrix

What is a determinant?

The determinant is a numerical value (positive or negative) calculated from the elements in a matrix and is used to find the inverse of a matrix
You can only find the determinant of a square matrix
The method for finding the determinant of a $2 cross times 2$ matrix is given by:

$bold italic A equals open parentheses table row a b row c d end table close parentheses rightwards double arrow det space bold italic A equals open vertical bar bold italic A close vertical bar equals a d minus b c$

Worked Example

Consider the matrix <img alt=”bold italic A equals open parentheses table row 3 cell negative 6 end cell row p 7 end table close parentheses” data-mathml='<math ><semantics><mrow><mi mathvariant=”bold-italic”>A</mi><mo>=</mo><mfenced><mtable><mtr><mtd><mn>3</mn></mtd><mtd><mo>-</mo><mn>6</mn></mtd></mtr><mtr><mtd><mi>p</mi></mtd><mtd><mn>7</mn></mtd></mtr></mtable></mfenced></mrow><annotation encoding=”application/vnd.wiris.mtweb-params+json”>{“language”:”en”,”fontFamily”:”Times New Roman”,”fontSize”:”18″}</annotation></semantics></math>’ height=”54″ role=”math” 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Further Maths: Core Pure -Edexcel-A Level

determinants-of-matrices

Determinant of a 2×2 matrix

What is a determinant?

Worked Example

Responses