Home
Class 10
MATHS
If x = 3 + 2 sqrt2, then find the value ...

If `x = 3 + 2 sqrt2`, then find the value of `x + (1)/(x)`

Text Solution

Verified by Experts

Given that `x = 3 + 2 sqrt2`
`:. (1)/(x) = (1)/(3 + 2 sqrt2) = (1)/(3+ 2 sqrt2) xx (3-2 sqrt2)/(3 - 2 sqrt2)`
`= (3-2sqrt2)/((3)^(2) - (2 sqrt2)^(2)) = (3 - 2 sqrt2)/(9 -8)`
`= (3 - 2 sqrt2)/(1) = 3 -2 sqrt2`
`:. x + (1)/(x) =3 + 2sqrt2 + 3 -2 sqrt2 = 6`
`:.` The required summation = 6
Promotional Banner

Topper's Solved these Questions

  • QUADRATIC SURDS

    CALCUTTA BOOK HOUSE|Exercise Exercise -3.1|20 Videos
  • QUADRATIC SURDS

    CALCUTTA BOOK HOUSE|Exercise Exercise -3.2|28 Videos
  • QUADRATIC EQUATION IN ONE VARIABLE

    CALCUTTA BOOK HOUSE|Exercise EXERCISE-1.5|40 Videos
  • RATIO AND PROPORTION

    CALCUTTA BOOK HOUSE|Exercise EXERCISE - 2.2 (Long Answer Type Questions)|19 Videos

Similar Questions

Explore conceptually related problems

If x= 3+ 2sqrt2 then find the value of x+1/x .

If x=7+4sqrt3 then find the value of x+(1)/(x)

If x = 2 + sqrt3 , then the value of x + (1)/(x) is

If x=3+2sqrt2 , then find the value of (sqrtx -""1/sqrtx)

If x=7 + 4sqrt3 , then find the value of x^3/(x^6+3x^3+1)

If x = sqrt3/2 then find the value of (sqrt(1+x) - sqrt(1-x))/(sqrt(1+x) + sqrt(1-x))

If x = 1/(2-sqrt3) then find the value of (x^(3) -2x^(2) -7x+2)

Given x = 1 + sqrt2 + sqrt3 , then find the value of (2x^4 - 8x^3 - 5x^2 + 26x - 28)

If 0 < x < pi/2 "and" cosx + sin x = sqrt2, then find the value of sin 3x.

If 2^(x+1 ) = 3^(1-x) then find the value of x.

CALCUTTA BOOK HOUSE-QUADRATIC SURDS-Exercise -3.2
  1. If x = 3 + 2 sqrt2, then find the value of x + (1)/(x)

    Text Solution

    |

  2. If x = root(3)(sqrt9 + 1) - root(3)(sqrt9-1), the value of x^(3) + 6x ...

    Text Solution

    |

  3. If x = 5 + 2 sqrt6 and xy =1, " then " (1)/(x^(2)) + (1)/(y^(2)) =

    Text Solution

    |

  4. The simpliest value of (sqrt5 (sqrt(3 - sqrt5)))/(sqrt2 + sqrt(7 - 3 s...

    Text Solution

    |

  5. (sqrt10 + sqrt18)/(sqrt18 - sqrt(3 - sqrt5)) =

    Text Solution

    |

  6. If sqrt2x = sqrt((sqrt3 + 1)/(sqrt3 -1)), then x^(2) -x=

    Text Solution

    |

  7. Rationalising factor of (root(3)(3) + root(3)(2)) is

    Text Solution

    |

  8. If (4 + sqrt15)^((3)/(2)) + (4 - sqrt15)^((3)/(2)) =k. sqrt10, then k ...

    Text Solution

    |

  9. If (sqrt(5 + 2sqrt6)- sqrt(5 - 2 sqrt6))/(sqrt(5 + 2 sqrt6)+ sqrt(5 - ...

    Text Solution

    |

  10. The value of sqrt(2+sqrt(2+ sqrt(2….oo))) is

    Text Solution

    |

  11. If x + 7 + 4 sqrt3, then sqrtx + (1)/(sqrtx) = 4

    Text Solution

    |

  12. root(5)((32)/(243)) is a surd

    Text Solution

    |

  13. show that (7)/(2^((1)/(2)) + 2^((1)/(4)) + 1) = 1 - 3.2^((1)/(4)) + 2....

    Text Solution

    |

  14. Write which one is a rational number and which one is a surd : root(6)...

    Text Solution

    |

  15. Express as like surds: root(6)(5), root(5)(6)

    Text Solution

    |

  16. Express as complete surds: 3 sqrt2, 2 root(3)(4)

    Text Solution

    |

  17. (a) If x gt a, y gt b and x + y = a + b, then find which one of (sqrtx...

    Text Solution

    |

  18. If x and y are rational and if x (3 + 2 sqrt2) - y sqrt2 = y(5 -3 sqrt...

    Text Solution

    |

  19. Rationalise the denominator: (a) (1)/(root(3)(3) + root(3)(2)), (b) ...

    Text Solution

    |

  20. Evaluate: (a) sqrt((x^(3))sqrt( y sqrt(x^(3)sqrt(y....oo)))) ,

    Text Solution

    |

  21. If 2x = a + sqrt((4b^(3) - a^(3))/(3a)) and 2y = a - sqrt((4b^(3) - a^...

    Text Solution

    |