English

Let Δ = apbqcr|apxbqycrz| = 16, then Δ1 = paapqbbqrccr|p+xa+xa+pq+yb+yb+qr+zc+zc+r| = 32. - Mathematics

Advertisements
Advertisements

Question

Let Δ = `|("a", "p", x),("b", "q", y),("c", "r", z)|` = 16, then Δ1 = `|("p" + x, "a" + x, "a" + "p"),("q" + y, "b" + y, "b" + "q"),("r" + z, "c" + z, "c" + "r")|` = 32.

Options

  • True

  • False

MCQ
True or False

Solution

This statement is True.

Explanation:

Given that Δ = `|("a", "p", x),("b", "q", y),("c", "r", z)|` = 16

L.H.S. Δ1 = `|("p" + x, "a" + x, "a" + "p"),("q" + y, "b" + y, "b" + "q"),("r" + z, "c" + z, "c" + "r")|`

C1 → C1 + C2 + C3

= `|("2p" + 2x + 2"a", "a" + x, "a" + "p"),(2"q" +2y + 2"b", "b" + y, "b" + "q"),(2"r" + 2z + 2"c", "c" + z, "c" + "r")|`

= `2|("p" + x + "a", "a" + x, "a" + "p"),("q" +y + "b", "b" + y, "b" + "q"),("r" + z + "c", "c" + z, "c" + "r")|`  ......[Taking 2 common from C1]

C1 → C1 – C2 = `2|("p", "a" + x, "a" + "p"),("q", "b" + y, "b" + "q"),("r", "c" + z, "c" + "r")|`

C3 → C3 – C2d = `2|("p", "a" + x, "a"),("q", "b" + y, "b"),("r", "c" + z, "c")|`

Splitting up C2

= `2|("p", "a", "a"),("q", "b", "b"),("r", "c", "c")| + 2|("p", x, "a"),("q", "y", "b"),("r", "z", "c")|`

= `2(0) + 2|("p", x, "a"),("q", y, "b"),("r", z, "c")|`

= `2|("p", x, "a"),("q", y, "b"),("r", z, "c")|`

⇒ `2|("a", "p", x),("b", "q", y),("c", "r", z)|`  ......(C1 ↔ C3 and C2 ↔ C3)

= 2 × 16

= 32

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Determinants - Exercise [Page 85]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 12
Chapter 4 Determinants
Exercise | Q 57 | Page 85

RELATED QUESTIONS

 

If ` f(x)=|[a,-1,0],[ax,a,-1],[ax^2,ax,a]| ` , using properties of determinants find the value of f(2x) − f(x).

 

Using properties of determinants, prove that

`|[x+y,x,x],[5x+4y,4x,2x],[10x+8y,8x,3x]|=x^3`


By using properties of determinants, show that:

`|(-a^2, ab, ac),(ba, -b^2, bc),(ca,cb, -c^2)| = 4a^2b^2c^2`


Using properties of determinants, prove that:

`|(3a, -a+b, -a+c),(-b+a, 3b, -b+c),(-c+a, -c+b, 3c)|`= 3(a + b + c) (ab + bc + ca)


Using properties of determinants, prove that:

`|(1, 1+p, 1+p+q),(2, 3+2p, 4+3p+2q),(3,6+3p,10+6p+3q)| =  1`                 


Using properties of determinants, prove that 

`|(a^2 + 2a,2a + 1,1),(2a+1,a+2, 1),(3, 3, 1)| = (a - 1)^3`


Prove the following using properties of determinants :

\[\begin{vmatrix}a + b + 2c & a & b \\ c & b + c + 2a & b \\ c & a & c + a + 2b\end{vmatrix} = 2\left( a + b + c \right) {}^3\]


Without expanding evaluate the following determinant:

`|(1, "a", "b" + "c"),(1, "b", "c" + "a"),(1, "c", "a" + "b")|`


Using properties of determinant show that

`|(1, log_x y, log_x z),(log_y x, 1, log_y z),(log_z x, log_z y, 1)|` = 0


If  `|(4 + x, 4 - x, 4 - x),(4 - x,4 + x,4 - x),(4 - x,4 - x, 4 + x)|` = 0, then find the values of x.


Answer the following question:

Without expanding determinant show that

`|("b" + "c", "bc", "b"^2"c"^2),("c" + "a", "ca", "c"^2"a"^2),("a" + "b", "ab", "a"^2"b"^2)|` = 0


Answer the following question:

Without expanding determinant show that

`|(l, "m", "n"),("e", "d", "f"),("u", "v", "w")| = |("n", "f", "w"),(l, "e", "u"),("m", "d", "v")|`


The value of `|(1, 1, 1),(""^"n""C"_1, ""^("n" + 2)"C"_1, ""^("n" + 4)"C"_1),(""^"n""C"_2, ""^("n" + 2)"C"_2, ""^("n" + 4)"C"_2)|` is 8.


Evaluate: `|(0, xy^2, xz^2),(x^2y, 0, yz^2),(x^2z, zy^2, 0)|`


Prove that: `|(y^2z^2, yz, y + z),(z^2x^2, zx, z + x),(x^2y^2, xy, x + y)|` = 0


Find the value of θ satisfying `[(1, 1, sin3theta),(-4, 3, cos2theta),(7, -7, -2)]` = 0


If `[(4 - x, 4 + x, 4 + x),(4 + x, 4 - x, 4 + x),(4 + x, 4 + x, 4 - x)]` = 0, then find values of x.


The number of distinct real roots of `|(sinx, cosx, cosx),(cosx, sinx, cosx),(cosx, cosx, sinx)|` = 0 in the interval `pi/4  x ≤ pi/4` is ______.


If A, B and C are angles of a triangle, then the determinant `|(-1, cos"C", cos"B"),(cos"C", -1, cos"A"),(cos"B", cos"A", -1)|` is equal to ______.


If cos2θ = 0, then `|(0, costheta, sin theta),(cos theta, sin theta,0),(sin theta, 0, cos theta)|^2` = ______.


If `abs ((2"x",5),(8, "x")) = abs ((6,-2),(7,3)),`  then the value of x is ____________.


Let P be any non-empty set containing p elements. Then, what is the number of relations on P?


In a third order matrix B, bij denotes the element in the ith row and jth column. If

bij = 0 for i = j

= 1 for > j

= – 1 for i < j

Then the matrix is


The A.M., H.M. and G.M. between two numbers are `144/15`, 15 and 12, but not necessarily in this order then, H.M., G.M. and A.M. respectively are


By using properties of determinant prove that `|(x+y,y+z,z+x),(z,x,y),(1,1,1)|` = 0.


Without expanding determinants, find the value of `|(10, 57, 107),(12, 64, 124),(15, 78, 153)|`


Without expanding evaluate the following determinant.

`|(1, a, b + c),(1, b, c + a),(1, c, a + b)|`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×