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Two roots of equation of 2x^(2)-7x+12=0 ...

Two roots of equation of `2x^(2)-7x+12=0` are `alpha " &" beta` then find `(alpha)/(beta) + (beta)/(alpha)=` ?

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To solve the equation \(2x^2 - 7x + 12 = 0\) and find the value of \(\frac{\alpha}{\beta} + \frac{\beta}{\alpha}\), where \(\alpha\) and \(\beta\) are the roots of the equation, we can follow these steps: ### Step 1: Identify the coefficients The given quadratic equation is: \[ 2x^2 - 7x + 12 = 0 \] Here, the coefficients are: - \(a = 2\) - \(b = -7\) - \(c = 12\) ### Step 2: Calculate the sum and product of the roots Using Vieta's formulas: - The sum of the roots \(\alpha + \beta\) is given by: \[ \alpha + \beta = -\frac{b}{a} = -\frac{-7}{2} = \frac{7}{2} \] - The product of the roots \(\alpha \beta\) is given by: \[ \alpha \beta = \frac{c}{a} = \frac{12}{2} = 6 \] ### Step 3: Express \(\frac{\alpha}{\beta} + \frac{\beta}{\alpha}\) We know that: \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha \beta} \] To find \(\alpha^2 + \beta^2\), we can use the identity: \[ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta \] ### Step 4: Calculate \(\alpha^2 + \beta^2\) Substituting the values we found: \[ \alpha^2 + \beta^2 = \left(\frac{7}{2}\right)^2 - 2 \times 6 \] Calculating \(\left(\frac{7}{2}\right)^2\): \[ \left(\frac{7}{2}\right)^2 = \frac{49}{4} \] Calculating \(2 \times 6\): \[ 2 \times 6 = 12 = \frac{48}{4} \] Now substituting back: \[ \alpha^2 + \beta^2 = \frac{49}{4} - \frac{48}{4} = \frac{1}{4} \] ### Step 5: Substitute into the expression Now we can substitute \(\alpha^2 + \beta^2\) and \(\alpha \beta\) into our expression: \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha \beta} = \frac{\frac{1}{4}}{6} = \frac{1}{4} \times \frac{1}{6} = \frac{1}{24} \] ### Final Answer Thus, the value of \(\frac{\alpha}{\beta} + \frac{\beta}{\alpha}\) is: \[ \frac{1}{24} \]
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ADVANCED MATHS BY ABHINAY MATHS ENGLISH-ALGEBRA THEORY-Example
  1. Find HCF of 10x^(3)-10x^(2)-5x + 9 " &" 30x^(3)-61x^(2)-24x + 10

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  2. Find the Quadratic equation whose one root is 3+ sqrt3

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  3. Two roots of equation of 2x^(2)-7x+12=0 are alpha " &" beta then find ...

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  4. What is the product of the roots of the equation x^(3)-sqrt3=0?

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  5. If the equations x^(2) + 2x -3=0 and x^(2) + 3x-m=0 have a common root...

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  6. For what value of m equation 4x^(2) + 6mx + 9=0 have equal roots

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  7. If alpha " & " beta are the roots of equation ax^(2) + bx + c = 0 then...

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  8. If alpha " & " beta are the roots of equation ax^(2) + bx + c = 0 then...

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  9. If alpha " & " beta are the roots of equation ax^(2) + bx + c= 0 then...

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  10. If sqrt(3x^(2)-12x + 19) + sqrt(3x^(2)-12x-11)= 16 then find sqrt(3x^...

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  11. If x=2 - 2^((1)/(3)) + 2^((2)/(3)) find the value of x^(3)-6x^(2) + 1...

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  12. If x-y= (x+y)/(9)= (xy)/(6) then value of xy= ?

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  13. If the ratio of roots of equation lx^(2) + nx + n= 0 is p: q then find...

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  14. If a+b+c=6, a^(2) +b^(2)+ c^(2)=16, find ab+bc +ca= ?

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  15. a +b+c= 3, (1)/(a) + (1)/(b) + (1)/(c )=2 a^(2) + b^(2) + c^(2)=6 fi...

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  16. If a^(3) + b^(3)=0 find a+b=

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  17. If a^(4) + b^(4) = a^(2) b^(2) find a^(6) + b^(6)

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  18. If (p)/(a) + (q)/(b) + (r )/(c )=1 " & " (a)/(p) + (b)/(q) + (c )/(r )...

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  19. Given x+y= 2z, then (x)/(x-z) + (z)/(y-z)= ?

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  20. Given x+y= 2z, then (x)/(x-z) + (z)/(y-z) =?

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