मराठी

If A= `[[1 2],[2 1]]` F (X) = X2 − 2x − 3, Show That F (A) = 0 - Mathematics

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प्रश्न

If\[A = \begin{bmatrix}1 & 2 \\ 2 & 1\end{bmatrix}\] f (x) = x2 − 2x − 3, show that f (A) = 0

बेरीज

उत्तर

Here,

`f (x) =x^2−2x−3`

`⇒f(A)=A^2−2A−3I_2`

Now,

`A^2=A A`

`⇒A^2=[[1    2],[2     1]] ,[[1     2],[2      1]]`

`⇒A^2= [[1+4       2+2],[2+2      4+1]]`

`⇒A^2= [[5    4],[4     5]]`

`f(A)=A^2−2A−3I_2`

⇒f(A)= `[[5       4],[4      5]]-2[[1     2],[2      1]]-3[[1         0],[0     1]]`

⇒f(A)=`[[5       4],[4      5]]-[[2     4],[4    2]]-[[3   0],[0    3]]`

⇒f(A)=`[[5-2-3         4-4-0],[4-4-0       5-2-3]]`

⇒f(A)= `[[5-5             0],[0                  5 -5]]`

⇒f(A)=0

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पाठ 5: Algebra of Matrices - Exercise 5.3 [पृष्ठ ४४]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 5 Algebra of Matrices
Exercise 5.3 | Q 37 | पृष्ठ ४४

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