मराठी

If A and B are invertible matrices, then which of the following is not correct? - Mathematics

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प्रश्न

If A and B are invertible matrices, then which of the following is not correct?

पर्याय

  • adj A = |A|.A–1

  • det(A)–1 = [det(A)]–1

  • (AB)–1 = B–1A–1

  • (A + B)–1 = B–1 + A–1

MCQ
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उत्तर

(A + B)–1 = B–1 + A–1 

Explanation:

If A and B are two invertible matrices then

(a) adj A = |A| · A–1 is correct

(b) det (A)–1 = [det(A)]–1 = `1/("det"("A"))` is correct

(c) Also, (AB)–1 = B–1A–1 is correct

(d) (A + B)–1 = `1/|"A" + "B"| * "adj"("A" + "B")`

∴ (A + B)–1 ≠ B–1 + A–1 

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पाठ 4: Determinants - Exercise [पृष्ठ ८२]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 4 Determinants
Exercise | Q 34 | पृष्ठ ८२

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