Home
Class 12
MATHS
If alpha, beta are roots of the equation...

If `alpha, beta` are roots of the equation `x^(2) + x + 1 = 0`, then the equation whose roots are `(alpha)/(beta) and (beta)/(alpha)`, is

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the equation whose roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\), given that \(\alpha\) and \(\beta\) are the roots of the equation \(x^2 + x + 1 = 0\). ### Step 1: Identify the coefficients of the original equation The given equation is: \[ x^2 + x + 1 = 0 \] Here, we can identify: - \(a = 1\) - \(b = 1\) - \(c = 1\) ### Step 2: Calculate the sum and product of the roots For a quadratic equation \(ax^2 + bx + c = 0\), the sum of the roots \(\alpha + \beta\) and the product of the roots \(\alpha \beta\) can be calculated as follows: - Sum of roots: \[ \alpha + \beta = -\frac{b}{a} = -\frac{1}{1} = -1 \] - Product of roots: \[ \alpha \beta = \frac{c}{a} = \frac{1}{1} = 1 \] ### Step 3: Form the new equation with roots \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\) The new roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\). We need to find their sum and product: - Sum of the new roots: \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha \beta} \] - Product of the new roots: \[ \frac{\alpha}{\beta} \cdot \frac{\beta}{\alpha} = 1 \] ### Step 4: Calculate \(\alpha^2 + \beta^2\) We can find \(\alpha^2 + \beta^2\) using the identity: \[ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta \] Substituting the known values: \[ \alpha^2 + \beta^2 = (-1)^2 - 2 \cdot 1 = 1 - 2 = -1 \] ### Step 5: Substitute the values into the sum of the new roots Now we substitute \(\alpha^2 + \beta^2\) and \(\alpha \beta\) into the sum of the new roots: \[ \frac{\alpha^2 + \beta^2}{\alpha \beta} = \frac{-1}{1} = -1 \] ### Step 6: Form the new quadratic equation Using the sum and product of the new roots, we can form the quadratic equation: \[ x^2 - \text{(sum of roots)} \cdot x + \text{(product of roots)} = 0 \] Substituting the values: \[ x^2 - (-1)x + 1 = 0 \implies x^2 + x + 1 = 0 \] ### Conclusion Thus, the equation whose roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\) is: \[ \boxed{x^2 + x + 1 = 0} \]

To solve the problem, we need to find the equation whose roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\), given that \(\alpha\) and \(\beta\) are the roots of the equation \(x^2 + x + 1 = 0\). ### Step 1: Identify the coefficients of the original equation The given equation is: \[ x^2 + x + 1 = 0 \] Here, we can identify: ...
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • TEST PAPER

    RESONANCE ENGLISH|Exercise CHEMISTRY|24 Videos
  • SEQUENCE & SERIES

    RESONANCE ENGLISH|Exercise EXERCISE -2 (PART-II : PREVIOUSLY ASKED QUESTION OF RMO)|3 Videos
  • TEST PAPERS

    RESONANCE ENGLISH|Exercise MATHEMATICS|259 Videos

Similar Questions

Explore conceptually related problems

If alpha and beta are the roots of the equation 2x^(2)-3x+1=0 , form the equation whose roots are (alpha)/(2beta+3) and (beta)/(2alpha+3) .

If alpha, beta are the roots of the equation x^(2)+7x+12=0 , then the equation whose roots are (alpha+beta)^(2) and (alpha-beta)^(2) is

If alpha, beta are roots of the equation ax^2 + bx + c = 0 then the equation whose roots are 2alpha + 3beta and 3alpha + 2beta is

If alpha and beta are the roots of the equation x^(2) + x+ 1 = 0, then what is the equation whose roots are alpha^(19) and beta^(7) ?

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

alpha and beta are the roots of the equation x^(2) - 3x + 5 = 0 , the equation whose roots are (1)/(alpha) and (1)/(beta) is:

Let alpha and beta be the roots of the equation x^(2)+ax+1=0, a ne0 . Then the equation whose roots are -(alpha+(1)/(beta)) and -((1)/(alpha)+beta) is

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

If alpha, beta be the roots of the equation x^2-px+q=0 then find the equation whose roots are q/(p-alpha) and q/(p-beta)

If alpha and beta are roots of the quadratic equation x ^(2) + 4x +3=0, then the equation whose roots are 2 alpha + beta and alpha + 2 beta is :