Home
Class 12
MATHS
Consider f(x)=x^2-3x+2 The area bounded ...

Consider `f(x)=x^2-3x+2` The area bounded by `|y|=|f(|x|)|,xge1` is A, then find the value of `3A+2`.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the area bounded by the curves defined by \( |y| = |f(|x|)| \) for \( x \geq 1 \), where \( f(x) = x^2 - 3x + 2 \). ### Step-by-step Solution: 1. **Find the Roots of \( f(x) \)**: We start by finding the roots of the function \( f(x) = x^2 - 3x + 2 \). \[ f(x) = 0 \implies x^2 - 3x + 2 = 0 \] Factoring gives: \[ (x-1)(x-2) = 0 \implies x = 1, 2 \] 2. **Determine the Vertex of the Parabola**: The vertex of the parabola can be found using the formula \( x = -\frac{b}{2a} \). Here, \( a = 1 \) and \( b = -3 \): \[ x = \frac{3}{2} \] Substituting \( x = \frac{3}{2} \) back into \( f(x) \): \[ f\left(\frac{3}{2}\right) = \left(\frac{3}{2}\right)^2 - 3\left(\frac{3}{2}\right) + 2 = \frac{9}{4} - \frac{9}{2} + 2 = -\frac{1}{4} \] 3. **Sketch the Graph of \( f(x) \)**: The graph of \( f(x) \) is a parabola opening upwards with roots at \( x = 1 \) and \( x = 2 \) and a vertex at \( \left(\frac{3}{2}, -\frac{1}{4}\right) \). 4. **Consider the Absolute Values**: For \( |y| = |f(|x|)| \), we need to consider the graph of \( f(x) \) for \( x \geq 1 \) and reflect it in the x-axis for negative values of \( y \). 5. **Calculate the Area for \( x \geq 1 \)**: We need to find the area between the curve and the x-axis from \( x = 1 \) to \( x = 2 \): \[ A = \int_{1}^{2} f(x) \, dx \] First, we compute the integral: \[ A = \int_{1}^{2} (x^2 - 3x + 2) \, dx \] Evaluating the integral: \[ = \left[ \frac{x^3}{3} - \frac{3x^2}{2} + 2x \right]_{1}^{2} \] Calculating at the bounds: \[ = \left( \frac{2^3}{3} - \frac{3 \cdot 2^2}{2} + 2 \cdot 2 \right) - \left( \frac{1^3}{3} - \frac{3 \cdot 1^2}{2} + 2 \cdot 1 \right) \] \[ = \left( \frac{8}{3} - 6 + 4 \right) - \left( \frac{1}{3} - \frac{3}{2} + 2 \right) \] \[ = \left( \frac{8}{3} - \frac{18}{3} + \frac{12}{3} \right) - \left( \frac{1}{3} - \frac{9}{6} + \frac{12}{6} \right) \] \[ = \left( \frac{2}{3} \right) - \left( \frac{1}{3} + \frac{3}{6} \right) \] \[ = \frac{2}{3} - \left( \frac{1}{3} + \frac{1}{2} \right) = \frac{2}{3} - \frac{5}{6} = \frac{4}{6} - \frac{5}{6} = -\frac{1}{6} \] Since we are interested in the area, we take the absolute value: \[ A = \frac{1}{6} \] 6. **Calculate \( 3A + 2 \)**: Finally, we compute \( 3A + 2 \): \[ 3A + 2 = 3 \cdot \frac{1}{6} + 2 = \frac{3}{6} + 2 = \frac{1}{2} + 2 = \frac{5}{2} \] ### Final Answer: \[ \boxed{\frac{5}{2}} \]
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • AREA OF BOUNDED REGIONS

    ARIHANT MATHS ENGLISH|Exercise Exercise (Subjective Type Questions)|16 Videos
  • AREA OF BOUNDED REGIONS

    ARIHANT MATHS ENGLISH|Exercise Area of bounded Regions Exercise 7: Subjective Type Questions|1 Videos
  • AREA OF BOUNDED REGIONS

    ARIHANT MATHS ENGLISH|Exercise Area of bounded Regions Exercise 5: Matching Type Questions|2 Videos
  • BIONOMIAL THEOREM

    ARIHANT MATHS ENGLISH|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|21 Videos

Similar Questions

Explore conceptually related problems

The area bounded by y = 2-|2-x| and y=3/|x| is:

Let f(x)=x-x^(2) and g(x)=ax . If the area bounded by f(x) and g(x) is equal to the area bounded by the curves x=3y-y^(2) and x+y=3 , then find the value of |[a]| : [Note: denotes the greatest integer less than or equal to k.]

If f(x)=3x^(2)+4x-1 , then find the approximate value of f(3.1) .

If the area bounded by the curve f(x)=x^(1//3)(x-1) and the x-axis is A, then the value of 28A is__.

The area bounded by the curve y=3/|x| and y+|2-x|=2 is

Consider y = x^(2) and f (x) where f (x), is a differentiable function satisfying f (x+1) + f (z-1) =f (x+z) AA x , z in R and f (0) =0,f '(0) =4. If area bounded by curve y = x^(2) and y=f(x) is Delta, find the value of ((3)/(16) Delta).

Consider f(x)= minimum (x+2, sqrt(4-x)), AA x le 4 . If the area bounded by y=f(x) and the x - axis is (22)/(k) square units, then the value of k is

Find the area bounded by the curve y=4x-x^2 , the x-axis and the ordinates x=1 and x=3 .

Find the continuous function f where (x^4-4x^2)lt=f(x)lt=(2x^2-x^3) such that the area bounded by y=f(x),y=x^4-4x^2dot then y-axis, and the line x=t , where (0lt=tlt=2) is k times the area bounded by y=f(x),y=2x^2-x^3 ,y-axis , and line x=t(w h e r e0lt=tlt=2)dot

Find the continuous function f where (x^4-4x^2)lt=f(x)lt=(2x^2-x^3) such that the area bounded by y=f(x),y=x^4-4x^2dot then y-axis, and the line x=t , where (0lt=tlt=2) is k times the area bounded by y=f(x),y=2x^2-x^3,y-a xi s , and line x=t(w h e r e0lt=tlt=2)dot