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प्रश्न
If A is an invertible matrix, then det (A−1) is equal to ____________ .
विकल्प
det (A)
\[\frac{1}{det \left( A \right)}\]
1
none of these
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उत्तर
\[\frac{1}{det \left( A \right)}\]
We know that for any invertible matrix A,
\[\left| A^{- 1} \right|\]
\[\frac{1}{\left| A \right|}\]
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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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- Hence, find the cost of one paper bag, one scrap book and one pastel sheet.
