मराठी

AAaA(aA)-1=1a A-1, where a is any real number and A is a square matrix. - Mathematics

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प्रश्न

`("aA")^-1 = 1/"a"  "A"^-1`, where a is any real number and A is a square matrix.

पर्याय

  • True

  • False

MCQ
चूक किंवा बरोबर
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उत्तर

This statement is True.

Explanation:

If A is a non-singular square matrix, then for any non-zero scalar ‘a‘, aA is invertible.

∴ `("aA") * (1/"a" "A"^-1) = "a" * 1/"a" * "A" * "A"^-1` = I

So, (aA) is inverse of `(1/"a" "A"^-1)`

⇒ `("aA")^-1 = 1/"a" "A"^-1`

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पाठ 4: Determinants - Exercise [पृष्ठ ८४]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 4 Determinants
Exercise | Q 49 | पृष्ठ ८४

संबंधित प्रश्‍न

Two schools A and B want to award their selected students on the values of sincerity, truthfulness and helpfulness. School A wants to award Rs x each, Rs y each and Rs z each for the three respective values to 3, 2 and 1 students, respectively with a total award money of Rs 1,600. School B wants to spend Rs 2,300 to award 4, 1 and 3 students on the respective values (by giving the same award money to the three values as before). If the total amount of award for one prize on each value is Rs 900, using matrices, find the award money for each value. Apart from these three values, suggest one more value which should be considered for an award.


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