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For given equation x^(2) -ax+b=0 , match...

For given equation `x^(2) -ax+b=0` , match conditions in column I with possible values in column II
`{:("column -I " , "Colum-II"),("(A) If roots differ by unity then " a^(2)" is equal to" , "(p) b(ab+2)"),("(B) If roots differ by unity then " 1 + a^(2) " is equal to " , "(q) 1 + 4b"),("(C) If one of the root be twice the other then " 2a^(2) " is equal to " , "(r) 2(1+2b)"),("(D) If the sum of roots of the equation equal to the sum of squares of their reciprocal then " a^(2) " is equal to " , "(s) 9b"):}`

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To solve the problem, we need to match the conditions in column I with the corresponding values in column II based on the given quadratic equation \(x^2 - ax + b = 0\). ### Step-by-Step Solution: **Step 1: Analyze Condition (A)** Condition (A) states: "If roots differ by unity then \(a^2\) is equal to". Let the roots be \(\alpha\) and \(\beta\). If they differ by unity, we can express this as: \[ \alpha - \beta = 1 \quad \text{or} \quad \beta - \alpha = 1 \] Assuming \(\alpha - \beta = 1\), we can square both sides: \[ (\alpha - \beta)^2 = 1^2 \implies \alpha^2 - 2\alpha\beta + \beta^2 = 1 \] Using the relationships: \[ \alpha + \beta = a \quad \text{and} \quad \alpha \beta = b \] We can rewrite \(\alpha^2 + \beta^2\) as: \[ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta = a^2 - 2b \] Substituting into our equation: \[ a^2 - 2b - 1 = 0 \implies a^2 = 2b + 1 \] Thus, we can express this as: \[ a^2 = 1 + 4b \quad \text{(after rearranging)} \] **Match:** (A) → (q) --- **Step 2: Analyze Condition (B)** Condition (B) states: "If roots differ by unity then \(1 + a^2\) is equal to". From the previous step, we found that: \[ a^2 = 1 + 4b \] Thus: \[ 1 + a^2 = 1 + (1 + 4b) = 2 + 4b \] This can be factored as: \[ 1 + a^2 = 2(1 + 2b) \] **Match:** (B) → (r) --- **Step 3: Analyze Condition (C)** Condition (C) states: "If one of the roots is twice the other then \(2a^2\) is equal to". Let \(\alpha\) be one root and \(\beta = 2\alpha\). Then: \[ \alpha + \beta = 3\alpha = a \quad \text{and} \quad \alpha \beta = 2\alpha^2 = b \] From \(3\alpha = a\), we have \(\alpha = \frac{a}{3}\). Substituting this into the product of the roots: \[ b = 2\left(\frac{a}{3}\right)^2 = \frac{2a^2}{9} \] Rearranging gives: \[ a^2 = \frac{9b}{2} \] Thus: \[ 2a^2 = 9b \] **Match:** (C) → (s) --- **Step 4: Analyze Condition (D)** Condition (D) states: "If the sum of roots equals the sum of squares of their reciprocals then \(a^2\) is equal to". We know: \[ \alpha + \beta = a \quad \text{and} \quad \frac{1}{\alpha} + \frac{1}{\beta} = \frac{\alpha + \beta}{\alpha\beta} = \frac{a}{b} \] The sum of squares of the reciprocals is: \[ \frac{1}{\alpha^2} + \frac{1}{\beta^2} = \frac{\beta^2 + \alpha^2}{\alpha^2\beta^2} = \frac{(\alpha + \beta)^2 - 2\alpha\beta}{(\alpha\beta)^2} \] Thus: \[ a = \frac{a^2 - 2b}{b^2} \] Cross-multiplying gives: \[ a b^2 = a^2 - 2b \implies a^2 = ab^2 + 2b \] Factoring out gives: \[ a^2 = b(ab + 2) \] **Match:** (D) → (p) --- ### Final Matches: - (A) → (q) - (B) → (r) - (C) → (s) - (D) → (p)
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