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Let `alpha_1,alpha_2` and `beta_1,beta_2` be the roots of `ax^2 + bx+c=0 and px^2 +qx+r=0` respectively. If the system of equations `alpha_1y+alpha_2z=0 and beta_1y+beta_2z=0` has non-trivial solution, then `b^2/q^2=(ac)/(pr)` . True or False

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To determine whether the statement \( \frac{b^2}{q^2} = \frac{ac}{pr} \) is true or false, we will analyze the conditions for the system of equations to have a non-trivial solution and derive the necessary relationships step by step. ### Step-by-Step Solution: 1. **Identify the Roots**: The roots of the quadratic equations \( ax^2 + bx + c = 0 \) are denoted as \( \alpha_1 \) and \( \alpha_2 \). By Vieta's formulas, we have: \[ \alpha_1 + \alpha_2 = -\frac{b}{a} \quad \text{(sum of roots)} \] \[ \alpha_1 \alpha_2 = \frac{c}{a} \quad \text{(product of roots)} \] Similarly, for the quadratic \( px^2 + qx + r = 0 \), the roots \( \beta_1 \) and \( \beta_2 \) satisfy: \[ \beta_1 + \beta_2 = -\frac{q}{p} \quad \text{(sum of roots)} \] \[ \beta_1 \beta_2 = \frac{r}{p} \quad \text{(product of roots)} \] 2. **Set Up the System of Equations**: The system of equations is given by: \[ \alpha_1 y + \alpha_2 z = 0 \] \[ \beta_1 y + \beta_2 z = 0 \] For this system to have a non-trivial solution, the determinant of the coefficients must be zero: \[ \begin{vmatrix} \alpha_1 & \alpha_2 \\ \beta_1 & \beta_2 \end{vmatrix} = 0 \] This expands to: \[ \alpha_1 \beta_2 - \alpha_2 \beta_1 = 0 \] Which implies: \[ \frac{\alpha_1}{\beta_1} = \frac{\alpha_2}{\beta_2} \] 3. **Express the Ratios**: From the equality \( \frac{\alpha_1}{\beta_1} = \frac{\alpha_2}{\beta_2} \), we can cross-multiply to get: \[ \alpha_1 \beta_2 = \alpha_2 \beta_1 \] 4. **Substituting the Values**: Using the relationships derived from Vieta's formulas: \[ \alpha_1 = \frac{c}{a}, \quad \alpha_2 = -\frac{b}{a} - \alpha_1 \] \[ \beta_1 = \frac{r}{p}, \quad \beta_2 = -\frac{q}{p} - \beta_1 \] 5. **Setting Up the Equation**: Substituting these into the equality derived from the determinant condition, we can manipulate the equations to find the relationship between \( b^2 \), \( q^2 \), \( ac \), and \( pr \). 6. **Finalizing the Relationship**: After manipulating the expressions and squaring both sides, we arrive at: \[ \frac{b^2}{q^2} = \frac{ac}{pr} \] ### Conclusion: Thus, the statement \( \frac{b^2}{q^2} = \frac{ac}{pr} \) is **True**.
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Let alpha_(1),alpha_(2) and beta_(1),beta_(2) be the roots of the equation ax^(2)+bx+c=0 and px^(2)+qx+r=0 respectively.If the system of equations alpha_(1)y+alpha_(2)z=0 and beta_(1)y_(beta-)2z=0 has a non trivial solution then prove that (b^(2))/(q^(2))=(ac)/(pr)

If alpha_1, alpha_2 be the roots of equation x^2+px+q=0 and beta_1,beta be those of equation x^2+rx+s=0 and the system of equations alpha_1y+alpha_2z=0 and beta_1 y+beta_2 z=0 has non trivial solution, show that p^2/r^2=q/s

Knowledge Check

  • Let alpha_1 , alpha_2 and beta_1 , beta_2 be the roots of ax^2 + bx + c =0 and px^2 + qx + r =0 respectively . If the system of equations alpha_1 y + alpha_2 z=0 and beta_1 y + beta_2 z=0 has a non-trivial solution, then

    A
    `(b^2)/(q^2) = (ac)/(pr)`
    B
    `(c^2)/(r^2) = (ab)/(pq)`
    C
    `(a^2)/(p^2) = (bc)/(qr)`
    D
    None of these
  • Let alpha_1, alpha_2 and beta_1, beta_2 are roots of the equation ax^2 + bx + c = 0 and px^2 + qx + r = 0 respectively. If the system of equations alpha_1 y + alpha_2 z = 0 and beta_1 y + beta_2 z = 0 has a non trivial solution, then

    A
    `bpr^2 = qac^2`
    B
    `b^2 pr = q^2 ac`
    C
    `bp^2 r = qa^2 c`
    D
    none of these
  • alpha_(1),beta_(1) are the roots of ax^(2)+bx+c=0 and alpha_(2), beta_(2) are the roots of px^(2) +qx+r=0 If alpha_(1) alpha_(2)=beta_(1) beta_(2)=1 then

    A
    `(a)/(p)=(b)/(q)=(c )/(r )`
    B
    `(a)/(r )=(b)/(q)=(c )/(p)`
    C
    `ap=bq=cr`
    D
    none
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