JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
The number of integral values of \(k\), for which one root of the equation \(2 x^2-8 x+k=0\) lies in the interval \((1,2)\) and its other root lies in the interval \((2,3)\), is :
- A \(2\)
- B \(0\)
- C \(1\)
- D \(3\)
Answer & Solution
Correct Answer
(C) \(1\)
Step-by-step Solution
Detailed explanation
\(2 x^2-8 x+k=0\) \(f (1) \cdot f (2) < 0\) and \(\quad f (2) \cdot f (3) < 0\) \(( k -6)( k -8) < 0\) and \(\quad ( k -8)( k -6)<0\) \(k \in(6,8) k \in(6,8)\) \(\text { integral value of } k =7\)
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