If the roots of the equation 2x2 - 5x + b = 0 are in the ratio of 2:3, then find the value of b?
Correct answer: A. 3
- A. 3
- B. 4
- C. 5
- D. 6Enrolling In Online Certification Courses
Explanation
If the roots are 2k and 3k, their sum is 5k = 5/2 because the sum of roots is 5/2, so k = 1/2. Their product is (2k)(3k) = 6k² = 6 x (1/2)² = 3/2, and since the product is b/2, b/2 = 3/2 gives b = 3. The likely mistake is choosing b = 4 by using the ratio as the actual roots rather than scaling them to get the required sum.
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