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If f(x) = |[x^2-4x+6,2x^2+4x+10,3x^2-2x+...

If `f(x) = |[x^2-4x+6,2x^2+4x+10,3x^2-2x+16],[x-2,2x+2,3x-1],[1,2,3]|` then find the value of `int_(-3)^3(x^2sinx)/(1+x^6)f(x) dx`.

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To solve the problem, we need to evaluate the integral \[ \int_{-3}^{3} \frac{x^2 \sin x}{1 + x^6} f(x) \, dx \] where \[ f(x) = \left| \begin{array}{ccc} x^2 - 4x + 6 & x - 2 & 1 \\ 2x^2 + 4x + 10 & 2x + 2 & 2 \\ 3x^2 - 2x + 16 & 3x - 1 & 3 \end{array} \right| \] ### Step 1: Simplifying the Determinant First, we simplify the determinant \( f(x) \). We can factor out constants from the columns of the determinant. Taking 2 out of the second column, we have: \[ f(x) = 2 \cdot \left| \begin{array}{ccc} x^2 - 4x + 6 & x - 2 & 1 \\ 2x^2 + 4x + 10 & 1 & 2 \\ 3x^2 - 2x + 16 & 3x - 1 & 3 \end{array} \right| \] ### Step 2: Row Operations Next, we perform row operations to simplify the determinant further. We can subtract the first column from the second and three times the first column from the third: \[ f(x) = 2 \cdot \left| \begin{array}{ccc} x^2 - 4x + 6 & x - 2 & 1 \\ 2x^2 + 4x + 10 & 2x + 2 - (x - 2) & 2 \\ 3x^2 - 2x + 16 & 3x - 1 - 3(x - 2) & 3 \end{array} \right| \] This gives us: \[ f(x) = 2 \cdot \left| \begin{array}{ccc} x^2 - 4x + 6 & 1 & 1 \\ 2x^2 + 4x + 10 & 6x - 1 & 2 \\ 3x^2 - 2x + 16 & 10x - 2 & 3 \end{array} \right| \] ### Step 3: Expanding the Determinant Now we can expand the determinant along the third row: \[ f(x) = 2 \cdot \left( 1 \cdot \left| \begin{array}{cc} 2x^2 + 4x + 10 & 6x - 1 \\ 3x^2 - 2x + 16 & 10x - 2 \end{array} \right| \right) \] Calculating the determinant of the 2x2 matrix: \[ = 2 \cdot \left( (2x^2 + 4x + 10)(10x - 2) - (6x - 1)(3x^2 - 2x + 16) \right) \] ### Step 4: Evaluating the Integral Now we can substitute \( f(x) \) back into the integral: \[ \int_{-3}^{3} \frac{x^2 \sin x}{1 + x^6} f(x) \, dx = 2 \int_{-3}^{3} \frac{x^2 \sin x}{1 + x^6} \, dx \] ### Step 5: Analyzing the Integrand Notice that \( x^2 \) and \( 1 + x^6 \) are even functions, while \( \sin x \) is an odd function. The product of an even function and an odd function is an odd function. Therefore, the integrand \[ \frac{x^2 \sin x}{1 + x^6} \] is an odd function. ### Step 6: Conclusion The integral of an odd function over a symmetric interval around zero is zero: \[ \int_{-3}^{3} \frac{x^2 \sin x}{1 + x^6} \, dx = 0 \] Thus, we conclude: \[ \int_{-3}^{3} \frac{x^2 \sin x}{1 + x^6} f(x) \, dx = 0 \] ### Final Answer The value of the integral is: \[ \boxed{0} \]
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ARIHANT MATHS ENGLISH-DETERMINANTS -Exercise (Subjective Type Questions)
  1. Prove that |{:(b+c,c,b),(c,c+a,a),(b,a,a+b):}| = 4 abc

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  2. Prove: |[a-b-c,2a,2a],[2b,b-c-a,2b],[2c,2c,c-a-b]|=(a+b+c)^3

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  3. Find the value of determinant |[sqrt((13))+sqrt(3),2sqrt(5),sqrt(5)],[...

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  4. Find the value of the determinant |(bc,ca, ab),( p, q, r),(1, 1, 1)|,w...

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  5. Without expanding the determinant at any stage prove that |{:(-5,3+5i...

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  6. Prove without expansion that |a h+bgga b+c h bf+b afh b+b c af+b cc bg...

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  7. In a triangleABC, if |(1,1,1),(1+sinA,1+sinB,1+sinC),(sinA+sin^2A,sinB...

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  8. The value of |{:(betagamma,betagamma'+beta'gamma,beta'gamma'),(gammaal...

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  9. If y=(u)/(v), where u & v are functions of 'x' show that v^(3)(d^(2)y)...

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  10. Show that the determinant Delta(x) given by Delta(x) = |{:(sin(x+al...

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  11. Evaluate |{:(.^(x)C(1),,.^(x)C(2),,.^(x)C(3)),(.^(y)C(1),,.^(y)C(2),,....

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  12. (i) Find maximum value of f(x)=|{:(1+sin^(2)x,cos^(2)x,4sin2x),(sin...

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  13. If f(x) = |[x^2-4x+6,2x^2+4x+10,3x^2-2x+16],[x-2,2x+2,3x-1],[1,2,3]| t...

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  14. If |A| = 2 and A = | (2x, 6) , (5x, 1)| then find the value of x

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  15. Show that in general there are three values of t for which the followi...

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  16. Find dy/dx if y=13x-y^2

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  17. If x, y, z are not all zero & if ax + by + cz=0, bx+ cy + az=0 & cx ...

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