The number of all possible positive integral values of $$\alpha $$ for which the roots of the quadratic equation, 6x2 $$-$$ 11x + $$\alpha $$ = 0 are rational numbers is :
JEE · Math · previous-year question
- A.3correct
- B.2
- C.4
- D.5
Answer
A. 3
Explanation
For rational D must be perfect square D = 121 $$-$$ 24$$\alpha $$ for 121 $$-$$ 24$$\alpha $$ to be perfect square a must be 3, 4, 5 So, ans $$\alpha $$ = 3
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