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If x=-4 is a root of a Delta=|(x,2,3),(1...

If `x=-4` is a root of a `Delta=|(x,2,3),(1,x,1),(3,2,x)|=0`, then find the other two roots.

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To solve the problem, we need to find the roots of the determinant equation given that one root is \( x = -4 \). The determinant is defined as: \[ \Delta = \begin{vmatrix} x & 2 & 3 \\ 1 & x & 1 \\ 3 & 2 & x \end{vmatrix} \] We need to set this determinant equal to zero and find the other roots. ### Step 1: Calculate the Determinant We will expand the determinant using the first row: \[ \Delta = x \begin{vmatrix} x & 1 \\ 2 & x \end{vmatrix} - 2 \begin{vmatrix} 1 & 1 \\ 3 & x \end{vmatrix} + 3 \begin{vmatrix} 1 & x \\ 3 & 2 \end{vmatrix} \] Calculating each of these 2x2 determinants: 1. \(\begin{vmatrix} x & 1 \\ 2 & x \end{vmatrix} = x^2 - 2\) 2. \(\begin{vmatrix} 1 & 1 \\ 3 & x \end{vmatrix} = x - 3\) 3. \(\begin{vmatrix} 1 & x \\ 3 & 2 \end{vmatrix} = 2 - 3x\) Now substituting these values back into the determinant: \[ \Delta = x(x^2 - 2) - 2(x - 3) + 3(2 - 3x) \] ### Step 2: Simplify the Expression Now we simplify the expression: \[ \Delta = x^3 - 2x - 2x + 6 + 6 - 9x \] Combining like terms: \[ \Delta = x^3 - 13x + 12 \] ### Step 3: Set the Determinant to Zero Now we set the determinant equal to zero: \[ x^3 - 13x + 12 = 0 \] ### Step 4: Factor the Polynomial Since we know that \( x = -4 \) is a root, we can factor \( x + 4 \) out of the polynomial. We will perform polynomial long division: 1. Divide \( x^3 - 13x + 12 \) by \( x + 4 \). - \( x^3 \div x = x^2 \) - Multiply \( x^2 \) by \( x + 4 \) gives \( x^3 + 4x^2 \) - Subtract: \( -4x^2 - 13x + 12 \) - Divide \( -4x^2 \div x = -4x \) - Multiply: \( -4x(x + 4) = -4x^2 - 16x \) - Subtract: \( 3x + 12 \) - Divide \( 3x \div x = 3 \) - Multiply: \( 3(x + 4) = 3x + 12 \) - Subtract: \( 0 \) Thus, we have: \[ x^3 - 13x + 12 = (x + 4)(x^2 - 4x + 3) \] ### Step 5: Factor the Quadratic Now we factor the quadratic \( x^2 - 4x + 3 \): \[ x^2 - 4x + 3 = (x - 3)(x - 1) \] ### Step 6: Write the Complete Factorization Putting it all together, we have: \[ (x + 4)(x - 3)(x - 1) = 0 \] ### Step 7: Find the Roots The roots of the equation are: 1. \( x = -4 \) 2. \( x = 3 \) 3. \( x = 1 \) ### Final Answer The other two roots are \( x = 3 \) and \( x = 1 \). ---
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CBSE COMPLEMENTARY MATERIAL-MATRICES AND DETERMINANTS-FOUR MARK QUESTIONS
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  2. If x,y and zinR, and Delta=|(x,x+y,x+y+z),(2x,5x+2y,7x+5y+2z),(3x,7x...

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  3. If |(1,a^2,a^4),(1,b^2,b^4),(1,c^2,c^4)|=k|(1,1,1),(a,b,c),(a^2,b^2,c^...

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  4. Evaluate the following: |[1,,a^2-bc],[1, b,b^2-ac],[1,c,c^2-ab]|

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  5. |(1,a^(2)+bc,a^(3)),(1,b^(2)+ac,b^(3)),(1,c^(2)+ab,c^(3))|=-(a-b)(b-c)...

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  6. Using properties of determinants, prove that following: |"a"+"b"+2...

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  7. |[a,b,c],[a-b,b-c,c-a],[b+c,c+a,a+b]|=a^3+b^3+c^3-3abc

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  8. Prove that : (i) |{:(a,c,a+c),(a+b,b,a),(b,b+c,c):}|=2 abc (ii) Pr...

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  9. |(b+c,c+a,a+b),(c+a,a+b,b+c),(a+b,b+c,c+a)|=2(3abc-a^(3)-b^(3)-c^(3))

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  10. Prove that | ((b+c)^2, a^2,a^2),(b^2,(c+a)^2,b^2),(c^2,c^2,(a+b)^2)|=2...

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  11. Given A=[(0,-1,2),(2,-2,0)]andB-[(0,1),(1,0),(1,1)]. Find the product ...

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  12. Using properties of determinants, solve the following for x: |x-2 ...

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  13. FInd x when |[x+a, a^2, a^3] , [x+b, b^2, b^3] , [x+c, c^2, c^3]|=0 wh...

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  14. Express the matrix [3-2-4 3-2-5-1 1 2] as the sum of a symmetric and s...

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  15. If x=-4 is a root of a Delta=|(x,2,3),(1,x,1),(3,2,x)|=0, then find th...

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  16. Using properties of determinants. Find the value of 'x' |(4-x,4+x,4+...

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  17. prove that |(1,x,x+1),(2x,x(x-1),x(x+1)),(3x(1-x),x(x-1)(x-2),x(x+1)(...

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  18. If f(x)=|a-1 0a x a-1a x^2a x a| , using properties of determinants...

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  19. If A=[(2,-1,1),(-1,2,-1),(1,-1,2)] show that A^(2)-5A+4I=0 Hence fin...

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  20. It A=[(-1,2,0),(-1,1,1),(0,1,0)] show that A^(2)=A^(-1)

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