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If (a + (1)/(a) ) ^(2) = 3 then the val...

If `(a + (1)/(a) ) ^(2) = 3` then the value of `a ^(6) - (1)/( a ^(6))` will be :

A

1

B

3

C

0

D

2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we start with the equation given: \[ \left(a + \frac{1}{a}\right)^2 = 3 \] ### Step 1: Expand the left-hand side Using the identity \((x + y)^2 = x^2 + y^2 + 2xy\), we can expand the left-hand side: \[ a^2 + 2\left(a \cdot \frac{1}{a}\right) + \frac{1}{a^2} = 3 \] This simplifies to: \[ a^2 + 2 + \frac{1}{a^2} = 3 \] ### Step 2: Rearrange the equation Now, we can rearrange this equation to isolate \(a^2 + \frac{1}{a^2}\): \[ a^2 + \frac{1}{a^2} = 3 - 2 = 1 \] ### Step 3: Find \(a^4 + \frac{1}{a^4}\) Next, we need to find \(a^4 + \frac{1}{a^4}\). We can use the identity: \[ \left(a^2 + \frac{1}{a^2}\right)^2 = a^4 + 2 + \frac{1}{a^4} \] Substituting \(a^2 + \frac{1}{a^2} = 1\): \[ 1^2 = a^4 + 2 + \frac{1}{a^4} \] This simplifies to: \[ 1 = a^4 + 2 + \frac{1}{a^4} \] Rearranging gives: \[ a^4 + \frac{1}{a^4} = 1 - 2 = -1 \] ### Step 4: Find \(a^6 - \frac{1}{a^6}\) Now we will find \(a^6 - \frac{1}{a^6}\). We can use the identity: \[ a^6 - \frac{1}{a^6} = \left(a^2 + \frac{1}{a^2}\right)\left(a^4 - \frac{1}{a^4}\right) \] We already have \(a^2 + \frac{1}{a^2} = 1\) and we found \(a^4 + \frac{1}{a^4} = -1\). Thus, we can find \(a^4 - \frac{1}{a^4}\): \[ a^4 - \frac{1}{a^4} = (a^4 + \frac{1}{a^4}) - 2\left(\frac{1}{a^4}\right) = -1 - 2 = -3 \] ### Step 5: Calculate \(a^6 - \frac{1}{a^6}\) Now substituting back into our equation: \[ a^6 - \frac{1}{a^6} = \left(a^2 + \frac{1}{a^2}\right)\left(a^4 - \frac{1}{a^4}\right) = 1 \cdot (-3) = -3 \] ### Final Answer Thus, the value of \(a^6 - \frac{1}{a^6}\) is: \[ \boxed{-3} \]
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MOTHERS-ALGEBRA -MULTIPLE CHOICE QUESTION
  1. If (a + (1)/(a) ) ^(2) = 3 then the value of a ^(6) - (1)/( a ^(6)) w...

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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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