हिंदी

A Matrix of Order 3 × 3 Has Determinant 2. What is the Value of |A (3i)|, Where I is the Identity Matrix of Order 3 × 3. - Mathematics

Advertisements
Advertisements

प्रश्न

A matrix of order 3 × 3 has determinant 2. What is the value of |A (3I)|, where I is the identity matrix of order 3 × 3.

उत्तर

Let A be the given matrix . Then, 
\[\left| A \right| = 2 \left[\text{ Order }= n = 3 \right] \] 
\[\left| I \right| = 1 \left[\text{ I is an identity matrix }\right]\] 
\[3\left( I \right) = 3\] 
\[\left| A3\left( I \right) \right| = \left| 3A \right| = 3^3 \left| A \right| \left[\text{ A being of order 3 }\right]\] 
\[ = 27 \times 2 = 54\] 
\[ \Rightarrow \left| A3\left( I \right) \right| = 54\] 

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 6: Determinants - Exercise 6.6 [पृष्ठ ९१]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.6 | Q 32 | पृष्ठ ९१

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

If A  = `[(1,1,-2),(2,1,-3),(5,4,-9)]`, Find |A|


Find values of x, if `|[2,3],[4,5]|=|[x,3],[2x,5]|`


Using the property of determinants and without expanding, prove that:

`|(x, a, x+a),(y,b,y+b),(z,c, z+ c)| = 0`


Let A be a square matrix of order 3 × 3, then | kA| is equal to

(A) k|A|

(B) k2 | A |

(C) k3 | A |

(D) 3k | A |


Use properties of determinants to solve for x:

`|(x+a, b, c),(c, x+b, a),(a,b,x+c)| = 0` and `x != 0` 


On expanding by first row, the value of the determinant of 3 × 3 square matrix
  \[A = \left[ a_{ij} \right]\text{ is }a_{11} C_{11} + a_{12} C_{12} + a_{13} C_{13}\] , where [Cij] is the cofactor of aij in A. Write the expression for its value on expanding by second column.

 

Let A = [aij] be a square matrix of order 3 × 3 and Cij denote cofactor of aij in A. If |A| = 5, write the value of a31 C31  +  a32 C32 a33 C33.


A matrix A of order 3 × 3 is such that |A| = 4. Find the value of |2 A|.


Which of the following is not correct?


Which of the following is not correct in a given determinant of A, where A = [aij]3×3.


Using matrices, solve the following system of linear equations :

x + 2y − 3z = −4
2x + 3y + 2z = 2
3x − 3y − 4z = 11


Without expanding, show that Δ = `|("cosec"^2theta, cot^2theta, 1),(cot^2theta, "cosec"^2theta, -1),(42, 40, 2)|` = 0


If x, y ∈ R, then the determinant ∆ = `|(cosx, -sinx, 1),(sinx, cosx, 1),(cos(x + y), -sin(x + y), 0)|` lies in the interval.


The determinant ∆ = `|(sqrt(23) + sqrt(3), sqrt(5), sqrt(5)),(sqrt(15) + sqrt(46), 5, sqrt(10)),(3 + sqrt(115), sqrt(15), 5)|` is equal to ______.


Prove tha `|("bc" - "a"^2, "ca" - "b"^2, "ab" - "c"^2),("ca" - "b"^2, "ab" - "c"^2, "bc" - "a"^2),("ab" - "c"^2, "bc" - "a"^2, "ca" - "b"^2)|` is divisible by a + b + c and find the quotient.


Let f(t) = `|(cos"t","t", 1),(2sin"t", "t", 2"t"),(sin"t", "t", "t")|`, then `lim_("t" - 0) ("f"("t"))/"t"^2` is equal to ______.


If A = `[(2, lambda, -3),(0, 2, 5),(1, 1, 3)]`, then A–1 exists if ______.


If x, y, z are all different from zero and `|(1 + x, 1, 1),(1, 1 + y, 1),(1, 1, 1 + z)|` = 0, then value of x–1 + y–1 + z–1 is ______.


There are two values of a which makes determinant, ∆ = `|(1, -2, 5),(2, "a", -1),(0, 4, 2"a")|` = 86, then sum of these number is ______.


If A is a matrix of order 3 × 3, then |3A| = ______.


If A is invertible matrix of order 3 × 3, then |A–1| ______.


`|(0, xyz, x - z),(y - x, 0, y  z),(z - x, z - y, 0)|` = ______.


If f(x) = `|((1 + x)^17, (1 + x)^19, (1 + x)^23),((1 + x)^23, (1 + x)^29, (1 + x)^34),((1 +x)^41, (1 +x)^43, (1 + x)^47)|` = A + Bx + Cx2 + ..., then A = ______.


If A and B are matrices of order 3 and |A| = 5, |B| = 3, then |3AB| = 27 × 5 × 3 = 405.


The maximum value of `|(1, 1, 1),(1, (1 + sintheta), 1),(1, 1, 1 + costheta)|` is `1/2`


`abs ((1 + "a", "b", "c"),("a", 1 + "b", "c"),("a", "b", 1 + "c")) =` ____________


If A = `[(1,0,0),(2,"cos x","sin x"),(3,"sin x", "-cos x")],` then det. A is equal to ____________.


Find the minor of the element of the second row and third column in the following determinant `[(2,-3,5),(6,0,4),(1,5,-7)]`


If `"abc" ne 0  "and" abs ((1 + "a", 1, 1),(1, 1 + "b", 1),(1,1,1 + "c")) = 0, "then"  1/"a" + 1/"b" + 1/"c" =` ____________.


Let A be a square matrix of order 2 x 2, then `abs("KA")` is equal to ____________.


For positive numbers x, y, z the numerical value of the determinant `|(1, log_x y, log_x z),(log_y x, 3, log_y z),(log_z x, log_z y, 5)|` is


The value of determinant `|(sin^2 13°, sin^2 77°, tan135°),(sin^2 77°, tan135°, sin^2 13°),(tan135°, sin^2 13°, sin^2 77°)|` is


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×