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If the equation x^(2)-3x+|3x-a|le0 is to...

If the equation `x^(2)-3x+|3x-a|le0` is to be satisfied by atleast one `xgt0`, then let Mbe the interval of values of a needed, then integral part of length of M is -----------

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To solve the inequality \( x^2 - 3x + |3x - a| \leq 0 \) for at least one \( x > 0 \), we will analyze the cases based on the expression inside the absolute value. ### Step 1: Analyze the cases for \( |3x - a| \) The absolute value \( |3x - a| \) can be split into two cases: 1. **Case 1:** \( 3x - a \geq 0 \) (i.e., \( x \geq \frac{a}{3} \)) - In this case, \( |3x - a| = 3x - a \). - The inequality becomes: \[ x^2 - 3x + (3x - a) \leq 0 \implies x^2 - a \leq 0 \] - This simplifies to: \[ x^2 \leq a \] - Thus, we have \( 0 < x \leq \sqrt{a} \). 2. **Case 2:** \( 3x - a < 0 \) (i.e., \( x < \frac{a}{3} \)) - In this case, \( |3x - a| = a - 3x \). - The inequality becomes: \[ x^2 - 3x + (a - 3x) \leq 0 \implies x^2 - 6x + a \leq 0 \] - This is a quadratic inequality in \( x \). ### Step 2: Find the roots of the quadratic \( x^2 - 6x + a = 0 \) The roots of the quadratic equation \( x^2 - 6x + a = 0 \) are given by: \[ x = \frac{6 \pm \sqrt{36 - 4a}}{2} = 3 \pm \sqrt{9 - a} \] Let the roots be \( r_1 = 3 - \sqrt{9 - a} \) and \( r_2 = 3 + \sqrt{9 - a} \). ### Step 3: Determine the conditions for \( x \) to be in the interval For the quadratic \( x^2 - 6x + a \leq 0 \) to have real roots, the discriminant must be non-negative: \[ 36 - 4a \geq 0 \implies a \leq 9 \] ### Step 4: Find the intersection of intervals For the inequality \( x^2 \leq a \) to hold, we need: - \( x \) must be in the interval \( \left(0, \sqrt{a}\right) \). - For the second case, \( x \) must be in the interval \( \left(r_1, r_2\right) \). To ensure that there is at least one \( x > 0 \) that satisfies both conditions, we need: \[ \frac{a}{3} < r_2 \quad \text{and} \quad r_1 < \sqrt{a} \] ### Step 5: Solve the inequalities 1. From \( \frac{a}{3} < r_2 \): \[ \frac{a}{3} < 3 + \sqrt{9 - a} \implies a < 9 + 3\sqrt{9 - a} \] This inequality will hold for \( a \) in the range \( (0, 9) \). 2. From \( r_1 < \sqrt{a} \): \[ 3 - \sqrt{9 - a} < \sqrt{a} \implies 3 < \sqrt{a} + \sqrt{9 - a} \] Squaring both sides gives: \[ 9 < a + 9 - a + 2\sqrt{a(9 - a)} \implies 0 < 2\sqrt{a(9 - a)} \implies a(9 - a) > 0 \] This is satisfied when \( 0 < a < 9 \). ### Step 6: Conclusion Thus, the interval \( M \) of values for \( a \) is \( (0, 9) \). The length of this interval \( M \) is \( 9 - 0 = 9 \). ### Final Answer The integral part of the length of \( M \) is \( \boxed{9} \).
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FIITJEE-APPLICATION OF DERIVATIVE-SOLVED PROBLEMS (OBJECTIVE)
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  2. The inequality x^(2)-3x gt tan^(-1) x is ture in

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  3. If f(x)=(sin^(2)x-1)^(n) (2+cos^(2)x), then x = pi/2 is a point of

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  4. Let f(x)=int(0)^(x)e^(t)(t-1)(t-2)dt. Then, f decreases in the interva...

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  5. Range of the function f(x) = (x-1)^(5)/(x^(5)-1) is

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  6. Range of the function f(x)= x^(2)-6x+5/x^(2)-5x+6 is

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  7. Range of the function f(x)= x cos( 1/x), xgt1

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  8. If both the critical points of f(x) = ax^(3)+bx^(2) +cx +d are -ve the...

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  9. The least number of imaginary roots of f(x) = ax^(6)+bx^(4)+cx^(2)+dx ...

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  10. Statement -1: f(x) = x^(3)-3x+1 =0 has one root in the interval [-2,2]...

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  11. If the equation x^(2)-3x+|3x-a|le0 is to be satisfied by atleast one x...

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  12. If f(x) is differentiable and strictly increasing function, then the v...

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  13. The set of all values of a for which the function f(x)=(a^2-3a+2)(cos...

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  14. The set of all points where f(x) is increasing in (a,b)cup(c, infty) t...

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  15. If f(x) = x^(3) + ax^(2) + bx+c = 0 has three distinct integral roots ...

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  16. Let x and y be positive real numbers such that y^(3) + y le x -x^(3) ...

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  17. Match the following : {:("List - I " , " List - II") ,("(P) If " x^(...

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  18. Which of the following options is the only Correct combination ?

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  19. Which of the following options is the only Correct combination ?

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  20. Which of the following options is the only Correct combination ?

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