Q51.If the equation x2 + bx + 45 = 0, b ∈R has conjugate complex roots and they satisfy |z + 1| = 2√10, then (1) b2 −b = 30 (2) b2 + b = 72 (3) b2 −b = 42 (4) b2 + b = 12
What This Question Tests
This question combines the concept of complex conjugate roots of quadratic equations with the modulus property of complex numbers, requiring derivation of the root and then solving for 'b'.
Concepts Tested
Formulas Used
For ax²+bx+c=0, roots are conjugate if coefficients are real
If z=x+iy, |z|=√(x²+y²)
📚 NCERT Sections This Tests
9.15 — Apply Mirror Equation And The Condition:
Physics Class 12 · Chapter 9
9.15 Apply mirror equation and the condition: (a) f < 0 (concave mirror); u < 0 (object on left) (b) f > 0; u < 0 (c) f > 0 (convex mirror) and u < 0 (d) f < 0 (concave mirror); f < u < 0 to deduce the desired result.
5.11 — Draw All The Isomers (Geometrical And Optical) Of:
Chemistry Class 11 · Chapter 5
5.11 Draw all the isomers (geometrical and optical) of: (i) [CoCl2(en)2] + (ii) [Co(NH3)Cl(en)2] 2+ (iii) [Co(NH3)2Cl2(en)]+
5.12 — Write All The Geometrical Isomers Of [Pt(Nh3)(Br)(Cl)(Py)] And How Many Of
Chemistry Class 11 · Chapter 5
5.12 Write all the geometrical isomers of [Pt(NH3)(Br)(Cl)(py)] and how many of these will exhibit optical isomers?
📋 Question Details
- Chapter
- Complex Numbers
- Topic
- Complex roots of quadratic equations and modulus
- Year
- 2020
- Shift
- 08 Jan Shift 1
- Q Number
- Q51
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 5: Complex Numbers and Quadratic Equations
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