Home
Class 12
MATHS
If alpha, beta, gamma and delta are the ...

If `alpha, beta, gamma and delta` are the roots of the equation `x ^(4) -bx -3 =0,` then an equation whose roots are `(alpha +beta+gamma)/(delta^(2)), (alpha +beta+delta)/(gamma^(2)), (alpha +delta+gamma)/(beta^(2)), and (delta +beta+gamma)/(alpha^(2)), ` is:

A

`3x ^(4) +bx+1=0`

B

`3x ^(4) -bx +1=0`

C

`3x ^(4) +bx ^(3) -1=0`

D

`3x ^(4) -bx ^(3) -1=0`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find an equation whose roots are given in terms of the roots of the original polynomial \( x^4 - bx - 3 = 0 \). Let's denote the roots of the original equation as \( \alpha, \beta, \gamma, \delta \). ### Step 1: Find the sum of the roots From Vieta's formulas, we know that for a polynomial of the form \( x^4 + 0x^3 + 0x^2 - bx - 3 = 0 \): - The sum of the roots \( \alpha + \beta + \gamma + \delta = 0 \). ### Step 2: Express \( \alpha + \beta + \gamma \) Using the result from Step 1: \[ \alpha + \beta + \gamma = -\delta \] ### Step 3: Calculate the new roots The new roots are given by: 1. \( \frac{\alpha + \beta + \gamma}{\delta^2} = \frac{-\delta}{\delta^2} = -\frac{1}{\delta} \) 2. \( \frac{\alpha + \beta + \delta}{\gamma^2} = \frac{-\gamma}{\gamma^2} = -\frac{1}{\gamma} \) 3. \( \frac{\alpha + \delta + \gamma}{\beta^2} = \frac{-\beta}{\beta^2} = -\frac{1}{\beta} \) 4. \( \frac{\delta + \beta + \gamma}{\alpha^2} = \frac{-\alpha}{\alpha^2} = -\frac{1}{\alpha} \) Thus, the new roots can be expressed as: \[ -\frac{1}{\delta}, -\frac{1}{\gamma}, -\frac{1}{\beta}, -\frac{1}{\alpha} \] ### Step 4: Form the new polynomial The roots of the new polynomial can be represented as: \[ x = -\frac{1}{\alpha} \Rightarrow \alpha = -\frac{1}{x} \] Substituting \( x \) with \( -\frac{1}{x} \) in the original polynomial \( x^4 - bx - 3 = 0 \): \[ \left(-\frac{1}{x}\right)^4 - b\left(-\frac{1}{x}\right) - 3 = 0 \] This simplifies to: \[ \frac{1}{x^4} + \frac{b}{x} - 3 = 0 \] Multiplying through by \( x^4 \) gives: \[ 1 + bx^3 - 3x^4 = 0 \] Rearranging gives: \[ 3x^4 - bx^3 - 1 = 0 \] ### Final Result The equation whose roots are \( -\frac{1}{\delta}, -\frac{1}{\gamma}, -\frac{1}{\beta}, -\frac{1}{\alpha} \) is: \[ 3x^4 - bx^3 - 1 = 0 \]
Promotional Banner

Topper's Solved these Questions

  • QUADRATIC EQUATIONS

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise EXERCISE (COMPREHENSION TYPE PROBLEMS)|23 Videos
  • QUADRATIC EQUATIONS

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise EXERCISE (MATCHING TYPE PROBLEMS)|4 Videos
  • QUADRATIC EQUATIONS

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise EXERCISE (SUBJECTIVE TYPE PROBLEMS)|45 Videos
  • PROBABILITY

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise Exercise -5 : Subjective Type problems|11 Videos
  • SEQUENCE AND SERIES

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise EXERCISE (SUBJECTIVE TYPE PROBLEMS)|21 Videos

Similar Questions

Explore conceptually related problems

If alpha, beta , gamma, delta are the roots of the equation x^4+x^2+1=0 then the equation whose roots are alpha^2, beta^2, gamma^2, delta^2 is

If alpha, beta, gamma, are the roots of the equation x^(3)+3x-1=0, then equation whose roots are alpha^(2),beta^(2),gamma^(2) is

If alpha, beta, gamma are the roots of the cubic equation x^(3)+qx+r=0 then the find equation whose roots are (alpha-beta)^(2),(beta-gamma)^(2),(gamma-alpha)^(2) .

If alpha,beta,gamma are the roots of the equation x^3-p x+q=0, then find the cubic equation whose roots are alpha/(1+alpha),beta/(1+beta),gamma/(1+gamma) .

If alpha, beta and gamma are the roots of the equation x^(3)+x+2=0 , then the equation whose roots are (alpha- beta)(alpha-gamma), (beta-gamma)(beta-gamma) and (gamma-alpha)(gamma-alpha) is

If alpha , beta , gamma are the roots of x^3 + px^2 + qx + r=0 form the equation whose roots are alpha beta , beta gamma , gamma alpha

If alpha , beta , gamma are the roots of x^3 -7x + 6 =0 the equation whose roots are alpha + beta , beta + gamma , gamma + alpha is

If alpha , beta , gamma are the roots of x^3 + 3x^2 -4x +2=0 then the equation whose roots are (1)/( alpha beta) ,(1)/( beta gamma) ,(1)/( gamma alpha) is

If alpha ,beta,gamma are the roots of x^3 -7x +6=0 then find the equation whose roots are (alpha-beta)^2 ,(beta-gamma)^2,(gamma-alpha)^2

If alpha , beta , gamma are the roots of the equation x^3 +px^2 + qx +r=0 then the coefficient of x in cubic equation whose roots are alpha ( beta + gamma ) , beta ( gamma + alpha) and gamma ( alpha + beta) is

VIKAS GUPTA (BLACK BOOK) ENGLISH-QUADRATIC EQUATIONS -EXERCISE (ONE OR MORE THAN ONE ANSWER IS/ARE CORRECT)
  1. Let f (x) =x ^(2) -4x +c AA x in R, where c is a real constant, then w...

    Text Solution

    |

  2. If 0 lt a lt b lt c and the roots alpha,beta of the equation ax^2 +...

    Text Solution

    |

  3. If x satisfies |x-1| + |x-2|+|x-3|gt6, then : i)x ∈ (−∞,1) ii)x ∈...

    Text Solution

    |

  4. If both roots of the quadratic equation ax ^(2)+x+b-a =0 are non real ...

    Text Solution

    |

  5. If a,b are two numbers such that a ^(2) +b^(2) =7 and a ^(3) + b^(3) =...

    Text Solution

    |

  6. The number of non-negative integral ordered pair(s) (x,y) for which (x...

    Text Solution

    |

  7. If alpha, beta, gamma and delta are the roots of the equation x ^(4) -...

    Text Solution

    |

  8. The value of 'k' for which roots of the equation 4x^2-2x+k=0 are comp...

    Text Solution

    |

  9. If a,b,c in R, then for which of the following graphs of the quadrati...

    Text Solution

    |

  10. If the equation ax^(2) + bx + c = 0, a,b, c, in R have non -real ro...

    Text Solution

    |

  11. If alpha and beta are the roots of the equation ax ^(2) + bx + c=0,a,b...

    Text Solution

    |

  12. The equation cos ^(2) x - sin x+lamda = 0, x in (0, pi//2) has roots t...

    Text Solution

    |

  13. If the equation ln (x^(2) +5x ) -ln (x+a +3)=0 has exactly one solutio...

    Text Solution

    |

  14. The number of non-negative integral ordered pair(s) (x,y) for which (x...

    Text Solution

    |

  15. If a lt 0, then the value of x satisfying x ^(2)-2a|x-a| -3a ^(2)=0 i...

    Text Solution

    |

  16. If 0 lt a lt b lt c and the roots alpha,beta of the equation ax^2 +...

    Text Solution

    |

  17. Solve : | x - 1| + |x - 2| + | x - 3 | gt 6

    Text Solution

    |

  18. The value of 'k' for which roots of the equation 4x^2-2x+k=0 are comp...

    Text Solution

    |

  19. Let alpha , beta, gamma, delta are roots of x ^(4) -12x ^(3) +lamda x ...

    Text Solution

    |

  20. If the points ((a^3)/((a-1))),(((a^2-3))/((a-1))),((b^3)/(b-1)),(((b^2...

    Text Solution

    |