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If alpha " & " beta are the roots of equ...

If `alpha " & " beta` are the roots of equation `ax^(2) + bx + c = 0` then find the Quadratic equation whose roots are `(1)/(alpha) " & " (1)/(beta)`

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To find the quadratic equation whose roots are \( \frac{1}{\alpha} \) and \( \frac{1}{\beta} \), we can follow these steps: ### Step 1: Identify the sum and product of the original roots The roots of the original quadratic equation \( ax^2 + bx + c = 0 \) are \( \alpha \) and \( \beta \). From Vieta's formulas, we know: - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) ### Step 2: Calculate the sum of the new roots The new roots are \( \frac{1}{\alpha} \) and \( \frac{1}{\beta} \). The sum of these new roots can be calculated as follows: \[ \frac{1}{\alpha} + \frac{1}{\beta} = \frac{\beta + \alpha}{\alpha \beta} \] Substituting the values from Step 1: \[ \frac{1}{\alpha} + \frac{1}{\beta} = \frac{-\frac{b}{a}}{\frac{c}{a}} = -\frac{b}{c} \] ### Step 3: Calculate the product of the new roots The product of the new roots \( \frac{1}{\alpha} \) and \( \frac{1}{\beta} \) is given by: \[ \frac{1}{\alpha} \cdot \frac{1}{\beta} = \frac{1}{\alpha \beta} \] Substituting the value from Step 1: \[ \frac{1}{\alpha} \cdot \frac{1}{\beta} = \frac{1}{\frac{c}{a}} = \frac{a}{c} \] ### Step 4: Form the new quadratic equation Using the sum and product of the new roots, we can now form the quadratic equation: \[ x^2 - \left(\text{sum of roots}\right)x + \left(\text{product of roots}\right) = 0 \] Substituting the values we calculated: \[ x^2 - \left(-\frac{b}{c}\right)x + \frac{a}{c} = 0 \] This simplifies to: \[ x^2 + \frac{b}{c}x + \frac{a}{c} = 0 \] To eliminate the fraction, we can multiply through by \( c \): \[ cx^2 + bx + a = 0 \] ### Final Result The quadratic equation whose roots are \( \frac{1}{\alpha} \) and \( \frac{1}{\beta} \) is: \[ cx^2 + bx + a = 0 \] ---
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ADVANCED MATHS BY ABHINAY MATHS ENGLISH-ALGEBRA THEORY-Example
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  2. If alpha " & " beta are the roots of equation ax^(2) + bx + c = 0 then...

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

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

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

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

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

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

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

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

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

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

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

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

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

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  16. If x+1/y =1 and y + 1/z =1 then find the value of z + 1/x

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  17. Given x+ (1)/(y)=1 and y + (1)/(z)=1 find xyz= ?

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  18. Given x+ (1)/(y)=1 and y + (1)/(z)=1 find (x+y+z) + ((1)/(x) + (1)/...

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  19. (x+ (1)/(y)) = (y+ (1)/(z))= (z + (1)/(x)) and (x ne y ne z) find xyz=...

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  20. If (a-b)/(c ) + (b+c)/(a) + (c-a)/(b)=1 and (b+ c ne a)

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