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Let A =`[[-1 1 -1],[3 -3 3],[5 5 5]]`And B =`[[0 4 3],[1 -3 -3],[-1 4 4]]` , Compute A2 − B2. - Mathematics

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प्रश्न

Let A =`[[-1            1               -1],[3         -3           3],[5           5             5]]`and B =`[[0                4                  3],[1              -3              -3],[-1               4                 4]]`

, compute A2 − B2.

 
योग

उत्तर

Given : A= `[[-1            1               -1],[3         -3           3],[5           5             5]]`

Now,

`A^(2)=A A`

`⇒A^(2)=[[-1           1        -1],[3          -3            3],[5               5                    5]]`  `[[-1          1           -1],[3         -3             3],[5              5              5]]`

`⇒A^(2)=[[1+3-5         -1-3-5          1+3-5],[-3-9+15             3+9+15           -3-9+15],[-5+15+25                 5-15+25            -5+15+25]]`

`⇒A^(2)=[[-1        -9           -1],[3          27            3],[35              15                 35]]`

`B^(2)=B    B`

`⇒B^(2)=[[0          4           3],[1         -3          -3],[-1             4             4]]` `[[0         4          3],[1        -3           -3],[-1        4           4]]`

`⇒B^(2)=[[0+4-3          0-12+12               0-12+12],[0-3+3             4+9-12            3+9-12],[0+4-4          -4-12+12            -3-12+16]]`

`⇒B^(2)= [[1         0             0],[0            1                0],[0            0              1]]`

`A^2−B^2 `

`⇒A^2−B^2= [[-1        -9           -1],[3            27             3],[35                15               35]]-[[1        0           0],[0         1          0],[0          0               1]]`

`⇒A^2−B^2= [[-1-1          -9-0        -1-0],[3-0          27-1                3-0],[35-0          15-0           35-1]]`

`⇒A^2−B^2= [[-2         -9           -1],[3              26               3],[35           15             34]]`

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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 15 | पृष्ठ ४२

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