JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
If the quadratic equation \((\lambda+2)x^2-3\lambda x+4\lambda=0\), \(\lambda \neq -2\), has two positive roots, then the number of possible integral values of \(\lambda\) is:
- A \(1\)
- B \(2\)
- C \(3\)
- D \(4\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
For the quadratic equation \((\lambda+2)x^2-3\lambda x+4\lambda=0\) to have two positive roots, the following three conditions must be satisfied: 1. Discriminant \(D \ge 0\) \((-3\lambda)^2 - 4(\lambda+2)(4\lambda) \ge 0\) \(9\lambda^2 - 16\lambda^2 - 32\lambda \ge 0\)…
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