मराठी

For the matrix A = [3211] find the numbers a and b such that A2 + aA + bI = O. - Mathematics

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प्रश्न

For the matrix A = `[(3,2),(1,1)]` find the numbers a and b such that A2 + aA + bI = O.

बेरीज

उत्तर

A2 + aA + bI = O

`= [(3,2),(1,1)] [(3,2),(1,1)] + "a" [(3,2),(1,1)] + "b" [(1,0),(0,1)] = [(0,0),(0,0)]`

`= [(9 + 2, 6 + 2),(3 + 1,2 + 1)] - [(3"a", 2"a"),("a","a")] + [("b",0),(0,"b")] = [(0,0),(0,0)]`

`= [(11 + 3"a" + "b", 8 + 2"a" + 0),(4 + "a" + 0, 3 + "a" + "b")] = [(0,0),(0,0)]`

4 + a = 0

a = -4

3 + a + b = 0

3 - 4 + b = 0

b = 1

`therefore` a = - 4, b = 1

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पाठ 4: Determinants - Exercise 4.5 [पृष्ठ १३२]

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एनसीईआरटी Mathematics [English] Class 12
पाठ 4 Determinants
Exercise 4.5 | Q 14 | पृष्ठ १३२

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