Q61.The number of integral values of m for which the quadratic expression (1 + 2m) x2 −2(1 + 3m)x + 4(1 + m), x ∈R is always positive, is (1) 7 (2) 3 (3) 6 (4) 8
What This Question Tests
The question tests the conditions for a quadratic expression to be always positive (leading coefficient > 0 and discriminant < 0) and solving inequalities for integer values.
Concepts Tested
Formulas Used
ax² + bx + c > 0 if a > 0 and D < 0
📚 NCERT Sections This Tests
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Physics Class 12 · Chapter 9
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📋 Question Details
- Chapter
- Quadratic Equations
- Topic
- Quadratic expressions always positive
- Year
- 2019
- Shift
- 12 Jan Shift 2
- Q Number
- Q61
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 5: Quadratic Equations
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