Q62.If the sum of the square of the roots of the equation x2 −(sin α −2)x −(1 + sin α) = 0 is least, then α is equal to (1) π (2) π 6 4 (3) π (4) π 3 2
What This Question Tests
This question involves using the relations between roots and coefficients of a quadratic equation and then minimizing a trigonometric expression using calculus.
Concepts Tested
Formulas Used
α+β = -b/a
αβ = c/a
α^2+β^2 = (α+β)^2 - 2αβ
d/dx(f(x)) = 0 for extremum
📚 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.
9.21 — At What Angle Should A Ray Of Light Be Incident On The Face Of A Prism
Physics Class 12 · Chapter 9
9.21 At what angle should a ray of light be incident on the face of a prism of refracting angle 60° so that it just suffers total internal reflection at the other face? The refractive index of the material of the prism is 1.524.
1.27 — If The Solubility Product Of Cus Is 6 × 10–16, Calculate The Maximum Molarity Of
Chemistry Class 11 · Chapter 1
1.27 If the solubility product of CuS is 6 × 10–16, calculate the maximum molarity of CuS in aqueous solution.
📋 Question Details
- Chapter
- Quadratic Equations
- Topic
- Relations between roots and coefficients
- Year
- 2012
- Shift
- 12 May Online
- Q Number
- Q62
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 5: Complex Numbers and Quadratic Equations
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