Home
Class 14
MATHS
If a+(1)/(a)=2, then the value of (a^(5)...

If `a+(1)/(a)=2`, then the value of `(a^(5)+(1)/(a^(5)))` will be

A

0

B

1

C

3

D

2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \( a^5 + \frac{1}{a^5} \) given that \( a + \frac{1}{a} = 2 \). ### Step-by-Step Solution: 1. **Start with the given equation**: \[ a + \frac{1}{a} = 2 \] 2. **Square both sides**: \[ \left(a + \frac{1}{a}\right)^2 = 2^2 \] This expands to: \[ a^2 + 2 + \frac{1}{a^2} = 4 \] Rearranging gives: \[ a^2 + \frac{1}{a^2} = 4 - 2 = 2 \] 3. **Now, cube both sides of the original equation**: \[ \left(a + \frac{1}{a}\right)^3 = 2^3 \] Expanding this gives: \[ a^3 + 3\left(a + \frac{1}{a}\right) + \frac{1}{a^3} = 8 \] Substituting \( a + \frac{1}{a} = 2 \): \[ a^3 + \frac{1}{a^3} + 3 \cdot 2 = 8 \] Simplifying: \[ a^3 + \frac{1}{a^3} + 6 = 8 \] Therefore: \[ a^3 + \frac{1}{a^3} = 8 - 6 = 2 \] 4. **Now we need to find \( a^5 + \frac{1}{a^5} \)**. We can use the identity: \[ a^5 + \frac{1}{a^5} = \left(a^3 + \frac{1}{a^3}\right)\left(a^2 + \frac{1}{a^2}\right) - \left(a + \frac{1}{a}\right) \] Substituting the values we found: \[ a^5 + \frac{1}{a^5} = (2)(2) - 2 \] Simplifying gives: \[ a^5 + \frac{1}{a^5} = 4 - 2 = 2 \] ### Final Answer: Thus, the value of \( a^5 + \frac{1}{a^5} \) is \( \boxed{2} \).
Promotional Banner

Topper's Solved these Questions

  • POWER, INDICES AND SURDS

    KIRAN PUBLICATION|Exercise Test Yourself|25 Videos
  • POWER, INDICES AND SURDS

    KIRAN PUBLICATION|Exercise Type -VI|17 Videos
  • PIPE AND CISTERN

    KIRAN PUBLICATION|Exercise TIPE-IV|9 Videos
  • PROFIT AND LOSS

    KIRAN PUBLICATION|Exercise TEST YOURSELF|23 Videos

Similar Questions

Explore conceptually related problems

If a + (1)/(a) =3, then the value of a ^(5) + (1)/(a ^(5)) is:

If 5a+ (1)/(3a) = 5 , then the value of 9a^(2)+(1)/(25a^(2)) is

If a=1/(a-5) then the value of a+1/a

If 5a+(1)/(3a)=5 , then value of 9a^(2)+(1)/(25a^(2)) is

The value of tan(2tan^(-1)(1/5))

If (x+1/x) =2 then the value of (x^5+1/x^5) is:

If x+1/(x)=5 , then the value of x^(2)+1/(x^(2)) is:

The value of (5)/(121^(-(1)/(2))) is

KIRAN PUBLICATION-POWER, INDICES AND SURDS-Type -VII
  1. If x=sqrt(3)+(1)/(sqrt(3)), then the value of (x-(sqrt(126))/(sqrt(42)...

    Text Solution

    |

  2. If 4x=sqrt(5)+2, then the value of (x-(1)/(16x)) is

    Text Solution

    |

  3. What is x, if x^(3)=1.5^(3)-0.9^(3)-2.43

    Text Solution

    |

  4. If ((1)/(5))^(3y)=0.008, then the value of (0.25)^(y) is

    Text Solution

    |

  5. If x=1+sqrt(2)+sqrt(3), then find the value of x^(2)-2x+4.

    Text Solution

    |

  6. If x=sqrt(2)+1, then the value of x^(4)-(1)/(x^(4)) is

    Text Solution

    |

  7. (1)/(sqrt(a))-(1)/(sqrt(b))=0, then the value of (1)/(a)+(1)/(b) is

    Text Solution

    |

  8. If x=(0.25)^((1)/(2)), y=(0.4)^(2), z=(0.216)^((1)/(3)), then

    Text Solution

    |

  9. If a+(1)/(a)=2, then the value of (a^(5)+(1)/(a^(5))) will be

    Text Solution

    |

  10. If x=2+sqrt(3), then the value of (x^(2)-x+1)/(x^(2)+x+1) is :

    Text Solution

    |

  11. If 3a=4b=6c and a+b+c=27sqrt(29) then sqrt(a^(2)+b^(2)+c^(2)) is equal...

    Text Solution

    |

  12. If (sqrt(3)+1)^(2)=x+sqrt(3)y, then the value of (x+y) is

    Text Solution

    |

  13. If p=9, q=sqrt(17) then the value of (p^(2)-q^(2))^((-1)/(3)) is equal...

    Text Solution

    |

  14. If sqrt(1+(x)/(144))=(13)/(12), then x equals to

    Text Solution

    |

  15. If a=sqrt(2)+1 and b=sqrt(2)-1, then the value of (1)/(a+1)+(1)/(b+1) ...

    Text Solution

    |

  16. If x=(1)/((sqrt(2)+1)) then the value of (x^(2)+2x-1) is

    Text Solution

    |

  17. If x+(1)/(x)=sqrt(13), then (3x)/((x^(2)-1)) equals to

    Text Solution

    |

  18. If x+sqrt(5)=5+sqrt(y) and x,y are positive integers , then the value ...

    Text Solution

    |

  19. If c+(1)/(c )=sqrt(3), then the value of c^(3)+(1)/(c^(3)) is equal to

    Text Solution

    |

  20. What would be the remainder when 10^(6)-12 is divided by 9 ?

    Text Solution

    |