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If A = `[[Ab B^2],[-a^2 -ab]]` , Show That A2 = O - Mathematics

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प्रश्न

If A = `[[ab,b^2],[-a^2,-ab]]` , show that A2 = O

 
योग

उत्तर

Given : A= `[[ab                           b^2],[-a^2           -ab]]`

Now,

`A^2=A   A`

`⇒A^2= [[ab         b^2],[-a^2     -ab]]  [[ab         b^2],[-a^2       -ab]]`

`⇒A^2=[[a^2b^2-a^2b^2             ab^3-ab^3],[-a^3b+a^3b               -a^2b^2+a^2b^2]]`

`⇒A^2[[0       0],[0        0]]`

`⇒A^2= 0`

Hence proved.

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अध्याय 5: Algebra of Matrices - Exercise 5.3 [पृष्ठ ४२]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 5 Algebra of Matrices
Exercise 5.3 | Q 10 | पृष्ठ ४२

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