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If 2x = 3 +(2)/(x) , then the value of...

If `2x = 3 +(2)/(x) , ` then the value of `(4x)/(x ^(2) -1 x -1)` is :

A

4

B

2

C

`8/5`

D

8

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AI Generated Solution

The correct Answer is:
To solve the equation \( 2x = 3 + \frac{2}{x} \) and find the value of \( \frac{4x}{x^2 - 1x - 1} \), we will follow these steps: ### Step 1: Solve for \( x \) Starting with the equation: \[ 2x = 3 + \frac{2}{x} \] We can multiply both sides by \( x \) to eliminate the fraction: \[ 2x^2 = 3x + 2 \] Rearranging this gives us: \[ 2x^2 - 3x - 2 = 0 \] ### Step 2: Factor the quadratic equation Next, we will factor the quadratic equation \( 2x^2 - 3x - 2 = 0 \). We need two numbers that multiply to \( 2 \times -2 = -4 \) and add to \( -3 \). The numbers \( -4 \) and \( 1 \) work: \[ 2x^2 - 4x + x - 2 = 0 \] Grouping the terms: \[ (2x^2 - 4x) + (x - 2) = 0 \] Factoring by grouping: \[ 2x(x - 2) + 1(x - 2) = 0 \] This gives us: \[ (2x + 1)(x - 2) = 0 \] ### Step 3: Find the values of \( x \) Setting each factor to zero gives: \[ 2x + 1 = 0 \quad \Rightarrow \quad x = -\frac{1}{2} \] \[ x - 2 = 0 \quad \Rightarrow \quad x = 2 \] ### Step 4: Substitute \( x \) into the expression Now we need to find the value of \( \frac{4x}{x^2 - 1x - 1} \). We will evaluate this for both values of \( x \). #### For \( x = 2 \): Calculating the denominator: \[ x^2 - 1x - 1 = 2^2 - 2 - 1 = 4 - 2 - 1 = 1 \] Calculating the expression: \[ \frac{4(2)}{1} = \frac{8}{1} = 8 \] #### For \( x = -\frac{1}{2} \): Calculating the denominator: \[ x^2 - 1x - 1 = \left(-\frac{1}{2}\right)^2 - \left(-\frac{1}{2}\right) - 1 = \frac{1}{4} + \frac{1}{2} - 1 = \frac{1}{4} + \frac{2}{4} - \frac{4}{4} = -\frac{1}{4} \] Calculating the expression: \[ \frac{4\left(-\frac{1}{2}\right)}{-\frac{1}{4}} = \frac{-2}{-\frac{1}{4}} = 2 \times 4 = 8 \] ### Conclusion In both cases, the value of \( \frac{4x}{x^2 - 1x - 1} \) is \( 8 \). ### Final Answer The value of \( \frac{4x}{x^2 - 1x - 1} \) is \( 8 \).
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MOTHERS-ALGEBRA -MULTIPLE CHOICE QUESTION
  1. If 2x = 3 +(2)/(x) , then the value of (4x)/(x ^(2) -1 x -1) is :

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  2. If (5 sqrt5 x^3-3 sqrt3 y^3) div (sqrt5x- sqrt3y)=(Ax^2+By^2+Cxy), the...

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  3. If x+y+z=19, x^2+y^2+z^2=133 and xz=y^2, then the difference between z...

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  4. If x^(4) + x^(-4) = 194 , x gt 0 then the value of ( x - 2) ^(2) i...

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  5. If 16x^2+9y^2 +4z^2= 24(x-y+z)-61, then the value of (xy + 2z) is : ...

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  6. If x + y + z = 19, xy + yz + zx = 114, then the value of sqrt(x^3+y^3+...

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  7. If [8(x+y)^3- 27(x-y)^3] div (5y-x) = Ax^2+Cy^2+Bxy, then the value of...

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  8. If a^(2) + b^(2) + 64c^(2) + 16c + 3 = 2(a+b), then the value of 4a^(7...

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  9. If x + y = 1 and xy(xy - 2) = 12, then the value of x^4+y^4 is: यदि ...

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  10. If (27x^3-343y^3) div (3x-7y)=Ax^2+By^2 +7Cyx, then the value of (4A -...

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  11. If a^2+b^2+c^2=21, and a + b + c = 7, then (ab + bc + ca) is equal to ...

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  12. If ab + bc + ca = 8 and a^2+b^2+c^2=20, then a possible value of 1/2 (...

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  13. If (8x^3-27y^3)div (2x-3y)= (Ax^2+Bxy+Cy^2), then the valueof (2A + B ...

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  14. If x = a + (1)/(a) and y = a - (1)/(a) then sqrt(x^(4) + y^(4) - 2x^(2...

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  15. If 2x^(2) + y^(2) + 6x - 2xy + 9 = 0, then the value of (4x^(3) - y^(3...

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  16. If x + y = 12 and xy = 27, x > y, then the value of (x^3-y^3) is: यद...

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  17. If x^2+y^2+z^2=133,xy +yz + zx = 114 and xyz = 216, then the value of ...

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  18. If 3 sqrt3 x^3-2sqrt2 y^3=(sqrt3x- sqrt2y) (Ax^2+Cxy+By^2), then the v...

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  19. If a + (1)/(a) = 3, then (a^(4) + (1)/(a^(4))) is equal to :

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  20. If a + b + c = 2, a^(2) + b^(2) + c^(2) = 26, then the value of a^(3) ...

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  21. If (x^3-2 sqrt2 y^3) div (x-sqrt2 y)= (Ax^2+Bxy+Cy^2), then, (2A+4 sqr...

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