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STATEMENT - 1 : If x^(2)+2x+3=0 and 7x^(...

STATEMENT - 1 : If `x^(2)+2x+3=0` and `7x^(2)+lx+k = 0` have a common roots, then `l+k = 35`. Given `l, k epsilon R`.
STATEMENT - 2 : If `a, b, c epsilon R` and roots of a quadratic equation `ax^(2)+bx+c=0` are imaginary then roots occurs in conjugate pair.

A

STATEMENT - 1 is True, STATEMENT- 2 is True , STATEMENT - 2 is a correct explanation for STATEMENT - 1

B

STATEMENT - 1 is True, STATEMENT - 2 is True , STATEMENT - 2 is NOT a correct explanation for STATEMENT - 1

C

STATEMENT -1 is True, STATEMENT - 2 is False

D

STATEMENT -1 is False, STATEMENT - 2 is True

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The correct Answer is:
To solve the problem, we need to analyze the two statements provided and derive the necessary conclusions step by step. ### Step 1: Analyze the first quadratic equation The first equation given is: \[ x^2 + 2x + 3 = 0 \] To find the roots, we can use the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \(a = 1\), \(b = 2\), and \(c = 3\). ### Step 2: Calculate the discriminant The discriminant \(D\) is given by: \[ D = b^2 - 4ac = 2^2 - 4 \cdot 1 \cdot 3 = 4 - 12 = -8 \] Since the discriminant is negative, the roots are imaginary. ### Step 3: Roots of the first equation The roots can be expressed as: \[ x = \frac{-2 \pm \sqrt{-8}}{2 \cdot 1} = \frac{-2 \pm 2i\sqrt{2}}{2} = -1 \pm i\sqrt{2} \] Let’s denote the roots as: \[ \alpha = -1 + i\sqrt{2}, \quad \beta = -1 - i\sqrt{2} \] ### Step 4: Analyze the second quadratic equation The second equation is: \[ 7x^2 + lx + k = 0 \] We need to find conditions for this equation to have a common root with the first equation. ### Step 5: Use Vieta's formulas From Vieta's formulas for the second equation: - The sum of the roots (\(\alpha + \beta\)) is given by: \[ \alpha + \beta = -\frac{l}{7} \] - The product of the roots (\(\alpha \beta\)) is given by: \[ \alpha \beta = \frac{k}{7} \] ### Step 6: Set up equations using known values From the first equation, we know: \[ \alpha + \beta = -2 \quad \text{and} \quad \alpha \beta = 3 \] Thus, we can set up the following equations: 1. \(-\frac{l}{7} = -2\) implies \(l = 14\) 2. \(\frac{k}{7} = 3\) implies \(k = 21\) ### Step 7: Calculate \(l + k\) Now, we can find \(l + k\): \[ l + k = 14 + 21 = 35 \] ### Conclusion for Statement 1 Thus, we have shown that if the two equations have a common root, then \(l + k = 35\) is indeed correct. ### Step 8: Analyze Statement 2 The second statement claims that if the roots of a quadratic equation \(ax^2 + bx + c = 0\) are imaginary, then they occur in conjugate pairs. This is a well-known property of polynomials with real coefficients. Therefore, this statement is also correct. ### Final Conclusion Both statements are correct.

To solve the problem, we need to analyze the two statements provided and derive the necessary conclusions step by step. ### Step 1: Analyze the first quadratic equation The first equation given is: \[ x^2 + 2x + 3 = 0 \] To find the roots, we can use the quadratic formula: ...
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