English

Let `A =[[2,-3],[-7,5]]` and `B=[[1,0],[2,-4]]` Verify That (Ab)T = Bt At - Mathematics

Advertisements
Advertisements

Question

Let  `A =[[2,-3],[-7,5]]` And `B=[[1,0],[2,-4]]` verify that 

(AB)T = BT AT

 
Sum

Solution

\[Given: \hspace{0.167em} A = \begin{bmatrix}2 & - 3 \\ - 7 & 5\end{bmatrix}\]

\[ A^T = \begin{bmatrix}2 & - 7 \\ - 3 & 5\end{bmatrix}\]

\[\]

\[B = \begin{bmatrix}1 & 0 \\ 2 & - 4\end{bmatrix} \]

\[\left( iv \right) \left( AB \right)^T = B^T A^T \]

\[ \Rightarrow \left( \begin{bmatrix}2 & - 3 \\ - 7 & 5\end{bmatrix}\begin{bmatrix}1 & 0 \\ 2 & - 4\end{bmatrix} \right)^T = \begin{bmatrix}1 & 2 \\ 0 & - 4\end{bmatrix} \begin{bmatrix}2 & - 7 \\ - 3 & 5\end{bmatrix}\]

\[ \Rightarrow \left( \begin{bmatrix}2 - 6 & 0 + 12 \\ - 7 + 10 & 0 - 20\end{bmatrix} \right)^T = \begin{bmatrix}2 - 6 & - 7 + 10 \\ 0 + 12 & 0 - 20\end{bmatrix}\]

\[ \Rightarrow \left( \begin{bmatrix}- 4 & 12 \\ 3 & - 20\end{bmatrix} \right)^T = \begin{bmatrix}- 4 & 3 \\ 12 & - 20\end{bmatrix}\]

\[ \Rightarrow \begin{bmatrix}- 4 & 3 \\ 12 & - 20\end{bmatrix} = \begin{bmatrix}- 4 & 3 \\ 12 & - 20\end{bmatrix}\]

\[ \therefore LHS = RHS\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Algebra of Matrices - Exercise 5.4 [Page 54]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 5 Algebra of Matrices
Exercise 5.4 | Q 1.4 | Page 54

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Compute the indicated products:

`[[a    b],[-b      a]][[a     -b],[b         a]]`


Evaluate the following:

`([[1              3],[-1    -4]]+[[3        -2],[-1         1]])[[1         3           5],[2            4               6]]`


Evaluate the following:

`[[],[1  2  3],[]]` `[[1     0      2],[2       0         1],[0          1       2]]` `[[2],[4],[6]]`


Evaluate the following:

`[[1     -1],[0            2],[2           3]]`  `([[1     0        2],[2        0        1]]-[[0             1                 2],[1           0                    2]])`


If A =  `[[4       2],[-1        1]]` 

, prove that (A − 2I) (A − 3I) = O

 

For the following matrices verify the associativity of matrix multiplication i.e. (AB) C = A(BC):

`A =-[[1             2         0],[-1        0           1]]`,`B=[[1       0],[-1        2],[0        3]]` and C= `[[1],[-1]]`


For the following matrices verify the associativity of matrix multiplication i.e. (ABC = A(BC):

`A=[[4       2        3],[1       1          2],[3         0          1]]`=`B=[[1        -1          1],[0         1            2],[2           -1          1]]` and  `C= [[1       2       -1],[3       0         1],[0         0         1]]` 


If A= `[[1        0           -2],[3        -1           0],[-2              1               1]]` B=,`[[0         5           -4],[-2          1             3],[-1          0              2]] and  C=[[1               5              2],[-1           1              0],[0          -1             1]]` verify that A (B − C) = AB − AC.


If \[A = \begin{bmatrix}3 & - 5 \\ - 4 & 2\end{bmatrix}\] , find A2 − 5A − 14I.


 If `[[2     3],[5      7]] [[1      -3],[-2       4]]-[[-4      6],[-9        x]]` find x.


\[A = \begin{bmatrix}3 & 1 \\ - 1 & 2\end{bmatrix}\]show that A2 − 5A + 7I = O use this to find A4.


If A=then find λ, μ so that A2 = λA + μI

 

Solve the matrix equations:

`[[],[x-5-1],[]][[1,0,2],[0,2,1],[2,0,3]] [[x],[4],[1]]=0`


If f (x) = x2 − 2x, find f (A), where A=


If `A=[[0,0],[4,0]]` find `A^16`


If `A=[[1,1],[0,1]] ,` Prove that `A=[[1,n],[0,1]]` for all positive integers n.


If\[A = \begin{bmatrix}a & b \\ 0 & 1\end{bmatrix}\], prove that\[A^n = \begin{bmatrix}a^n & b( a^n - 1)/a - 1 \\ 0 & 1\end{bmatrix}\] for every positive integer n .


Three shopkeepers AB and C go to a store to buy stationary. A purchases 12 dozen notebooks, 5 dozen pens and 6 dozen pencils. B purchases 10 dozen notebooks, 6 dozen pens and 7 dozen pencils. C purchases 11 dozen notebooks, 13 dozen pens and 8 dozen pencils. A notebook costs 40 paise, a pen costs Rs. 1.25 and a pencil costs 35 paise. Use matrix multiplication to calculate each individual's bill.

 

Let  `A =[[2,-3],[-7,5]]` And `B=[[1,0],[2,-4]]` verify that 

(A − B)T = AT − BT


If A is an m × n matrix and B is n × p matrix does AB exist? If yes, write its order.

 

Given an example of two non-zero 2 × 2 matrices A and such that AB = O.

 

If  \[A = \begin{bmatrix}\cos x & - \sin x \\ \sin x & \cos x\end{bmatrix}\]  , find AAT

 

If \[A = \begin{bmatrix}1 & 1 \\ 1 & 1\end{bmatrix}\] satisfies A4 = λA, then write the value of λ.

 

 


If \[A = \begin{bmatrix}\cos \alpha & - \sin \alpha \\ \sin \alpha & \cos \alpha\end{bmatrix}\] is identity matrix, then write the value of α.


If I is the identity matrix and A is a square matrix such that A2 = A, then what is the value of (I + A)2 = 3A?


For a 2 × 2 matrix A = [aij] whose elements are given by 

\[a_{ij} = \frac{i}{j}\] , write the value of a12.
 

If A is a square matrix such that A2 = A, then write the value of 7A − (I + A)3, where I is the identity matrix.


If A and B are two matrices such that AB = A and BA = B, then B2 is equal to


If S = [Sij] is a scalar matrix such that sij = k and A is a square matrix of the same order, then AS = SA = ? 


If \[A = \begin{bmatrix}1 & - 1 \\ 2 & - 1\end{bmatrix}, B = \begin{bmatrix}a & 1 \\ b & - 1\end{bmatrix}\]and (A + B)2 = A2 + B2,   values of a and b are


If A is a square matrix such that A2 = A, then (I + A)3 − 7A is equal to


If A = `[(2, -1, 3),(-4, 5, 1)]` and B = `[(2, 3),(4, -2),(1, 5)]`, then ______.


If X = `[(3, 1, -1),(5, -2, -3)]` and Y = `[(2, 1, -1),(7, 2, 4)]`, find 2X – 3Y


If X = `[(3, 1, -1),(5, -2, -3)]` and Y = `[(2, 1, -1),(7, 2, 4)]`, find A matrix Z such that X + Y + Z is a zero matrix


Give an example of matrices A, B and C such that AB = AC, where A is nonzero matrix, but B ≠ C.


If A and B are square matrices of the same order, then (kA)′ = ______. (k is any scalar)


If A and B are square matrices of the same order, then [k (A – B)]′ = ______.


If A `= [(1,-2,1),(2,1,3)]` and B `= [(2,1),(3,2),(1,1)],` then (AB)T is equal


If A = `[(a, b),(b, a)]` and A2 = `[(α, β),(β, α)]`, then ______.


Let a, b, c ∈ R be all non-zero and satisfy a3 + b3 + c3 = 2. If the matrix A = `((a, b, c),(b, c, a),(c, a, b))` satisfies ATA = I, then a value of abc can be ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×