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Find the adjoint of the matrices. [1-12235-201] - Mathematics

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प्रश्न

Find the adjoint of the matrices.

`[(1,-1,2),(2,3,5),(-2,0,1)]`

योग

उत्तर

`"A" = [(1,-1,2),(2,3,5),(-2,0,1)]`

A11 = 3, A12 = - 12, A13 = 6

A21 = 1, A22 = 5, A23 = 2.

A31 = - 11, A32 = -1, A33 = 5

adj A `=  [("A"_11,"A"_21,"A"_21),("A"_12,"A"_22,"A"_32),("A"_13,"A"_23,"A"_33)]^"T"`

`= [(3,-12,6),(1,5,-2),(-11,-1,5)]^"T"`

`= [(3,1,-11),(-12,5,-1),(6,2,5)]`

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अध्याय 4: Determinants - Exercise 4.5 [पृष्ठ १३१]

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एनसीईआरटी Mathematics [English] Class 12
अध्याय 4 Determinants
Exercise 4.5 | Q 2 | पृष्ठ १३१

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