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Find the equation whose roots are (alpha...

Find the equation whose roots are `(alpha)/(beta) and (beta)/(alpha)`, where `alpha and beta` are the roots of the equation `x^(2)+2x+3=0`.

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To find the equation whose roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\), where \(\alpha\) and \(\beta\) are the roots of the equation \(x^2 + 2x + 3 = 0\), we can follow these steps: ### Step 1: Find the roots \(\alpha\) and \(\beta\) The roots of the quadratic equation \(x^2 + 2x + 3 = 0\) can be found using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \(a = 1\), \(b = 2\), and \(c = 3\). Calculating the discriminant: \[ b^2 - 4ac = 2^2 - 4 \cdot 1 \cdot 3 = 4 - 12 = -8 \] Since the discriminant is negative, the roots are complex: \[ x = \frac{-2 \pm \sqrt{-8}}{2 \cdot 1} = \frac{-2 \pm 2i\sqrt{2}}{2} = -1 \pm i\sqrt{2} \] Thus, the roots are: \[ \alpha = -1 + i\sqrt{2}, \quad \beta = -1 - i\sqrt{2} \] ### Step 2: Calculate \(\alpha + \beta\) and \(\alpha \beta\) Using Vieta's formulas: \[ \alpha + \beta = -\frac{b}{a} = -2 \] \[ \alpha \beta = \frac{c}{a} = 3 \] ### Step 3: Find the sum and product of the new roots The new roots are \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\). **Sum of the new roots:** \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha \beta} \] Using the identity \(\alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta\): \[ \alpha^2 + \beta^2 = (-2)^2 - 2 \cdot 3 = 4 - 6 = -2 \] Thus, \[ \frac{\alpha^2 + \beta^2}{\alpha \beta} = \frac{-2}{3} \] **Product of the new roots:** \[ \frac{\alpha}{\beta} \cdot \frac{\beta}{\alpha} = 1 \] ### Step 4: Form the new quadratic equation Using the sum and product of the roots, we can write the quadratic equation: \[ x^2 - \left(\text{sum of roots}\right)x + \text{product of roots} = 0 \] Substituting the values: \[ x^2 - \left(-\frac{2}{3}\right)x + 1 = 0 \] This simplifies to: \[ x^2 + \frac{2}{3}x + 1 = 0 \] To eliminate the fraction, multiply the entire equation by 3: \[ 3x^2 + 2x + 3 = 0 \] ### Final Answer The required quadratic equation is: \[ 3x^2 + 2x + 3 = 0 \]
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ICSE-QUADRATIC EQUATIONS-EXERCISE 10 (c)
  1. If the sum of the roots of the equation x^(2)-px+q=0 be m times their ...

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  2. If one root of the equation x^(2)+ax+8=0 is 4 while the equation x^(2)...

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  3. Find the value of a for which one root of the quadratic equation (a^(2...

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  4. If alpha,beta are the roots of the equation ax^(2)-bx+b=0, prove that ...

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  5. If alpha and beta are the roots of the equation x^(2)+x-7=0, form the ...

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  6. If alpha and beta are the roots of the equation 2x^(2)+3x+2=0, find th...

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  7. Find the equation whose roots are (alpha)/(beta) and (beta)/(alpha), w...

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

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  9. If a ne b and a^(2)=5a-3,b^(2)=5b-3, then form that equation whose roo...

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  10. Given that alpha and beta are the roots of the equation x^(2)=x+7. (...

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  11. Given that alpha and beta are the roots of the equation x^(2)-x+7=0, f...

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  12. Given that alpha and beta are the roots of the equation 2x^(2)-3x+4=0,...

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  13. The roots of the quadratic equation x^(2)+px+8=0 are alpha and beta. ...

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  14. If the roots of x^(2)-bx+c=0 be two consecutive integers, then find th...

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  15. The roots of the equation px^(2)-2(p+1)x+3p=0 are alpha and beta. If a...

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  16. The roots of the equation ax^(2)+bx+c=0 are alpha and beta. Form the q...

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  17. Two candidates attempt to solve a quadratic equation of the form x^(2)...

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  18. Given that alpha and beta are the roots of the equation x^(2)=7x+4, ...

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  19. The ratio of the roots of the equation x^(2)+alphax+alpha+2=0 is 2. fi...

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  20. If (1-p) is a root of the quadratic equation x^(2)+px+(1-p)=0, then it...

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