मराठी

If A = [0-xx0], B = [0110] and x2 = –1, then show that (A + B)2 = A2 + B2. - Mathematics

Advertisements
Advertisements

प्रश्न

If A = `[(0, -x),(x, 0)]`, B = `[(0, 1),(1, 0)]` and x2 = –1, then show that (A + B)2 = A2 + B2

बेरीज

उत्तर

We have, A = `[(0, -x),(x, 0)]`, B = `[(0, 1),(1, 0)]` and x2 = –1

∴ (A + B) = `[(0, -x + 1),(x + 1, 0)]`

∴ (A + B)2 = `[(0, -x + 1),(x + 1, 0)] [(0, -x + 1),(x + 1, 0)]`

= `[(1 - x^2, 0),(0, 1 - x^2)]`  .....(i)

Also, A2 = A · A

= `[(0, -x),(x, 0)] [(0, -x),(x, 0)]`

= `[(-x^2, 0),(0, -x^2)]`

And B2 = B · B

= `[(0, 1),(1, 0)] [(0, 1),(1, 0)]`

= `[(1, 0),(0, 1)]`

∴ A2 + B2 = `[(-x^2, 0),(0, -x^2)] + [(1, 0),(0, 1)]`

= `[(1 - x^2, 0),(0, 1 - x^2)]`  ......(ii)

From equations (i) and (ii), we have

(A + B)2 = A2 + B2

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 3: Matrices - Exercise [पृष्ठ ५७]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 3 Matrices
Exercise | Q 34 | पृष्ठ ५७

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

if  `A=[[2,0,0],[0,2,0],[0,0,2]]` then A6=  ......................


If `A=[[1,2,2],[2,1,2],[2,2,1]]` ,then show that `A^2-4A-5I=0` and hence find A-1.


Let `A = [(2,4),(3,2)] , B = [(1,3),(-2,5)], C = [(-2,5),(3,4)]`

Find  A + B


Compute the following sums:

`[[3   -2],[1           4]]+ [[-2         4 ],[1           3]]`


Compute the following sums:

`[[2    1   3],[0   3   5],[-1   2   5]]`+ `[[1 -2     3],[2            6        1],[0   -3       1]]`


Let A = `[[2,4],[3,2]]`, `B=[[1,3],[-2,5]]`and `c =[[-2,5],[3,4]]`.Find each of the following: 2A − 3B


If A = diag (2 − 59), B = diag (11 − 4) and C = diag (−6 3 4), find

B + C − 2A


X − Y =`[[1      1       1],[1        1          0],[1         0          0]]` and X + Y = `[[3        5         1],[-1       1           1],[11       8           0]]`find X and Y.


If A = `[[2      -2],[4             2],[-5          1]],B=[[8             0],[4      -2],[3          6]]`

, find matrix X such that 2A + 3X = 5B.

 

Find xy satisfying the matrix equations

`[[X-Y               2            -2],[4                        x                6]]+[[3        -2                2],[1         0            -1]]=[[                6                       0                             0],[         5                       2x+y                5]]`


Find xyz and t, if

`2[[x         5],[z         t]]+[[x           6],[-1          2t]]=[[7            14],[15        14]]`


If X and Y are 2 × 2 matrices, then solve the following matrix equations for X and Y.

`2X + 3Y = [[2,3],[4,0]], 3X+2Y = [[-2,2],[1,-5]]`


If w is a complex cube root of unity, show that

`([[1         w          w^2],[w            w^2             1],[w^2           1             w]]+[[w          w^2          1],[w^2             1               w],[w            w^2              1]])[[1],[w],[w^2]]=[[0],[0],[0]]`


 Let  \[A = \begin{bmatrix}3 & 2 & 7 \\ 1 & 4 & 3 \\ - 2 & 5 & 8\end{bmatrix} .\] Find matrices X and Y such that X + Y = A, where X is a symmetric and Y is a skew-symmetric matrix

 


Define a symmetric matrix. Prove that for
\[A = \begin{bmatrix}2 & 4 \\ 5 & 6\end{bmatrix}\], A + AT is a symmetric matrix where AT is the transpose of A.
 

 


Express the matrix \[A = \begin{bmatrix}3 & - 4 \\ 1 & - 1\end{bmatrix}\]  as the sum of a symmetric and a skew-symmetric matrix.

 

 


If \[A = \begin{bmatrix}\cos x & \sin x \\ - \sin x & \cos x\end{bmatrix}\] , find x satisfying 0 < x < \[\frac{\pi}{2}\] when A + AT = I


Find the values of x and y, if \[2\begin{bmatrix}1 & 3 \\ 0 & x\end{bmatrix} + \begin{bmatrix}y & 0 \\ 1 & 2\end{bmatrix} = \begin{bmatrix}5 & 6 \\ 1 & 8\end{bmatrix}\]


If  \[2\begin{bmatrix}3 & 4 \\ 5 & x\end{bmatrix} + \begin{bmatrix}1 & y \\ 0 & 1\end{bmatrix} = \begin{bmatrix}7 & 0 \\ 10 & 5\end{bmatrix}\] , find x − y.

 

 


The trace of the matrix \[A = \begin{bmatrix}1 & - 5 & 7 \\ 0 & 7 & 9 \\ 11 & 8 & 9\end{bmatrix}\], is


Addition of matrices is defined if order of the matrices is ______.


Let A = `[(1, 2),(-1, 3)]`, B = `[(4, 0),(1, 5)]`, C = `[(2, 0),(1, -2)]` and a = 4, b = –2. Show that: A + (B + C) = (A + B) + C


Let A = `[(1, 2),(-1, 3)]`, B = `[(4, 0),(1, 5)]`, C = `[(2, 0),(1, -2)]` and a = 4, b = –2. Show that: (a + b)B = aB + bB


If A = `[(1, 2),(4, 1)]`, find A2 + 2A + 7I.


Matrix multiplication is ______ over addition.


Let A = `[(1, -1),(2, α)]` and B = `[(β, 1),(1, 0)]`, α, β ∈ R. Let α1 be the value of α which satisfies (A + B)2 = `A^2 + [(2, 2),(2, 2)]` and α2 be the value of α which satisfies (A + B)2 = B2 . Then |α1 – α2| is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×