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If A and B are square matrices of order 3 such that |A| = –1 and |B| = 3, find the value of |3AB| - Mathematics

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प्रश्न

If A and B are square matrices of order 3 such that |A| = –1 and |B| = 3, find the value of |3AB|

योग
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उत्तर

Given |A| = –1

|B| = 3

Given A and B are square matrices of order 3.

∴ |kAB| = k3 |AB|

Here k = 3

∴ |3AB| = 33 |AB|

= 27 |AB|

= 27(–1)(3)

= – 81

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Determinants
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Matrices and Determinants - Exercise 7.2 [पृष्ठ ३०]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 7 Matrices and Determinants
Exercise 7.2 | Q 17 | पृष्ठ ३०

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