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ax2 + x + b = 0 সমীকরণটির মূল সমান হবে যদি 

  1. b2 = 4a
  2. b2 < 4a
  3. b2 > 4a
  4. ab = 1/4

Answer (Detailed Solution Below)

Option 4 : ab = 1/4
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Detailed Solution

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প্রদত্ত সমীকরণ,

⇒ ax2 + x + b = 0

যদি মূল সমান হয় তাহলে, b2 - 4ac = 0 

⇒ b2 = 4ac

এখানে,

b = 1, a = a and c = b

তাহলে,

⇒ 1 = 4ab

⇒ ab = 1/4

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-> The RRB Group D Exam Date will be announced on the official website. It is expected that the Group D Exam will be conducted in August-September 2025. 

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