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If x + (1)/(x) =-2, then the value of x ...

If `x + (1)/(x) =-2,` then the value of `x ^(7) + (1)/(x^(7))`

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0

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1

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2

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`-2`

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To solve the equation \( x + \frac{1}{x} = -2 \) and find the value of \( x^7 + \frac{1}{x^7} \), we can follow these steps: ### Step-by-Step Solution: 1. **Given Equation**: We start with the equation: \[ x + \frac{1}{x} = -2 \] 2. **Finding \( x \)**: We can rearrange the equation to find \( x \). Let's multiply both sides by \( x \) (assuming \( x \neq 0 \)): \[ x^2 + 1 = -2x \] Rearranging gives us: \[ x^2 + 2x + 1 = 0 \] This can be factored as: \[ (x + 1)^2 = 0 \] Thus, we find: \[ x + 1 = 0 \quad \Rightarrow \quad x = -1 \] 3. **Finding \( x^7 + \frac{1}{x^7} \)**: Now that we have \( x = -1 \), we can calculate \( x^7 + \frac{1}{x^7} \): \[ x^7 = (-1)^7 = -1 \] \[ \frac{1}{x^7} = \frac{1}{(-1)^7} = -1 \] Therefore: \[ x^7 + \frac{1}{x^7} = -1 + (-1) = -2 \] 4. **Final Answer**: The value of \( x^7 + \frac{1}{x^7} \) is: \[ \boxed{-2} \]
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MOTHERS-ALGEBRA -MULTIPLE CHOICE QUESTION
  1. If x + (1)/(x) =-2, then the value of x ^(7) + (1)/(x^(7))

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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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