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Solve the following inequailities : 4a...

Solve the following inequailities :
`4abs(x^(2)-1)+abs(x^(2)-4)ge6`

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To solve the inequality \( 4|x^2 - 1| + |x^2 - 4| \geq 6 \), we will break it down into different cases based on the expressions inside the absolute values. ### Step 1: Identify critical points The expressions inside the absolute values are \( x^2 - 1 \) and \( x^2 - 4 \). We need to find the points where these expressions are zero: - \( x^2 - 1 = 0 \) gives \( x = \pm 1 \) - \( x^2 - 4 = 0 \) gives \( x = \pm 2 \) Thus, the critical points are \( -2, -1, 1, 2 \). ### Step 2: Create intervals The critical points divide the number line into the following intervals: 1. \( (-\infty, -2) \) 2. \( [-2, -1) \) 3. \( [-1, 1) \) 4. \( [1, 2) \) 5. \( [2, \infty) \) ### Step 3: Analyze each interval We will analyze the expression \( 4|x^2 - 1| + |x^2 - 4| \) in each of these intervals. #### Interval 1: \( (-\infty, -2) \) In this interval: - \( x^2 - 1 \geq 0 \) (since \( x^2 \geq 4 \)) - \( x^2 - 4 \geq 0 \) Thus, \( |x^2 - 1| = x^2 - 1 \) and \( |x^2 - 4| = x^2 - 4 \). The inequality becomes: \[ 4(x^2 - 1) + (x^2 - 4) \geq 6 \] \[ 4x^2 - 4 + x^2 - 4 \geq 6 \] \[ 5x^2 - 8 \geq 6 \] \[ 5x^2 \geq 14 \implies x^2 \geq \frac{14}{5} \] Thus, \( x \leq -\sqrt{\frac{14}{5}} \). #### Interval 2: \( [-2, -1) \) In this interval: - \( x^2 - 1 \geq 0 \) - \( x^2 - 4 < 0 \) Thus, \( |x^2 - 1| = x^2 - 1 \) and \( |x^2 - 4| = -(x^2 - 4) = 4 - x^2 \). The inequality becomes: \[ 4(x^2 - 1) + (4 - x^2) \geq 6 \] \[ 4x^2 - 4 + 4 - x^2 \geq 6 \] \[ 3x^2 \geq 6 \implies x^2 \geq 2 \] Thus, \( x \in [-2, -\sqrt{2}] \). #### Interval 3: \( [-1, 1) \) In this interval: - \( x^2 - 1 < 0 \) - \( x^2 - 4 < 0 \) Thus, \( |x^2 - 1| = -(x^2 - 1) = 1 - x^2 \) and \( |x^2 - 4| = 4 - x^2 \). The inequality becomes: \[ 4(1 - x^2) + (4 - x^2) \geq 6 \] \[ 4 - 4x^2 + 4 - x^2 \geq 6 \] \[ 8 - 5x^2 \geq 6 \implies -5x^2 \geq -2 \implies x^2 \leq \frac{2}{5} \] Thus, \( x \in [-\sqrt{\frac{2}{5}}, \sqrt{\frac{2}{5}}] \). #### Interval 4: \( [1, 2) \) In this interval: - \( x^2 - 1 \geq 0 \) - \( x^2 - 4 < 0 \) Thus, \( |x^2 - 1| = x^2 - 1 \) and \( |x^2 - 4| = 4 - x^2 \). The inequality becomes: \[ 4(x^2 - 1) + (4 - x^2) \geq 6 \] \[ 4x^2 - 4 + 4 - x^2 \geq 6 \] \[ 3x^2 \geq 6 \implies x^2 \geq 2 \] Thus, \( x \in [\sqrt{2}, 2) \). #### Interval 5: \( [2, \infty) \) In this interval: - \( x^2 - 1 \geq 0 \) - \( x^2 - 4 \geq 0 \) Thus, \( |x^2 - 1| = x^2 - 1 \) and \( |x^2 - 4| = x^2 - 4 \). The inequality becomes: \[ 4(x^2 - 1) + (x^2 - 4) \geq 6 \] \[ 4x^2 - 4 + x^2 - 4 \geq 6 \] \[ 5x^2 - 8 \geq 6 \implies 5x^2 \geq 14 \implies x^2 \geq \frac{14}{5} \] Thus, \( x \geq \sqrt{\frac{14}{5}} \). ### Step 4: Combine the results The solution to the inequality is the union of the results from all intervals: - From interval 1: \( (-\infty, -\sqrt{\frac{14}{5}}] \) - From interval 2: \( [-2, -\sqrt{2}] \) - From interval 3: \( [-\sqrt{\frac{2}{5}}, \sqrt{\frac{2}{5}}] \) - From interval 4: \( [\sqrt{2}, 2) \) - From interval 5: \( [\sqrt{\frac{14}{5}}, \infty) \) Thus, the final solution is: \[ x \in (-\infty, -\sqrt{\frac{14}{5}}] \cup [-2, -\sqrt{2}] \cup [-\sqrt{\frac{2}{5}}, \sqrt{\frac{2}{5}}] \cup [\sqrt{2}, 2) \cup [\sqrt{\frac{14}{5}}, \infty) \]
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FIITJEE-FUNCTION-EXERCISES
  1. Solve the following inequalities: ((x-1)(x-2))/((2x-5)(x+4))lt0

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  2. Solve the following inequailities : abs(x-1)+2abs(x+1)+abs(x-2)le8

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  3. Solve the following inequailities : 4abs(x^(2)-1)+abs(x^(2)-4)ge6

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  4. Solve the inequality x[x]-x^(3)-3[x]+3xgt0 where [.] denote greatest i...

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  5. Solve: [x]^3 - 2[x] +1 = 0,

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  6. Solve the inequality [x]^2-3[x]+2lt=0.

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  7. If y=3[x]+1=2[x-3]+5, find the value of [x+y]

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  8. Find the domain of following functions: f(x)=1/(sqrt(abs(x)-x^(2)))

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  9. Find the domain of following functions: f(x)=1/(sqrt(x-[x]))

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  10. Find the range of f(x)=x^(2)-3x+2,0lexle4

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  11. Find the range of f(x)=abs(sinx)+abs(cosx)0lexlepi

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  12. The range of the function sin^2x-5sinx -6 is

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  13. Find the domain and range of f(x)=log(1/sqrt([cosx]-[sinx])). [.] deno...

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  14. Find the domain of the function f(x)=3/([x/2])-5^(cos^(-1)x^(2))+( (2x...

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  15. Let f(x)=abs(sinx),0lexlepi and g(x)=abs(cosx)-pi//2lexlepi//2. Find f...

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  16. If f(x)={{:(x^(2),xle0),(x,xgt0):} and g(x)=-absx,x inR, then find fog...

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  17. State the following function is one-one or not and why? f:RtoR defin...

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  18. State which of the following functions are one-one and why? f:R^(+)t...

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  19. State which of the following functions are one-one and why? f:R.{1}t...

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  20. State which of the following function are onto and why? f:RtoR defin...

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