Let α and β α < &bet

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

41.

Let z, z2 and z3 be non-zero complex numbers satisfying

z2 = iz, where i =  - 1.

Consider the following statements :

  1. z1z2z3 is purely imaginary
  2. z1z2 + z2z3 + z3z1 is purely real

Which of the above statements is/are correct ?

  • 1 only

  • 2 only

  • Both 1 and 2

  • Neither 1 nor 2


42.

Let, z be a complex number satisfying

z - 4z - 8 = 1 and zz - 2 = 32

What is z = ?

  • 6

  • 12

  • 18

  • 36


43.

Let, z be a complex number satisfying

z - 4z - 8 = 1 and zz - 2 = 32

What is z - 6z + 6 = ?

  • 3

  • 2

  • 1

  • 0


44.

Let α and β α < β be the roots of the equation x2 + bx + c = 0, where, b > 0 and c < 0

Consider the following :

1. β < - α2. β < α

Which of the above is/are correct ?

  • 1 only

  • 2 only

  • both 1 and 2

  • neither 1 nor 2


Advertisement
Advertisement

45.

Let α and β α < β be the roots of the equation x2 + bx + c = 0, where, b > 0 and c < 0

Consider the following :

1. α + β + αβ > 02. α2β + β2α > 0

Which of the above is/are correct ?

  • 1 only

  • 2 only

  • both 1 and 2

  • neither 1 nor 2


C.

both 1 and 2

      α + β = - b, α . β = cAs,          b> 0 and c < 0So, α + β < 0 and α . β < 0and from question,       α < β α is negative number β is positive number              α + β < 0 and αβ < 0  α + β + αβ < 0and α2β + β2α = αβα + β > 0


Advertisement
46.

If one root of the equation (l - m)x2 + lx+ 1 = is double the other and l is real, then what is thgreatest value of ?

  •  - 98

  • 98

  • - 89

  • 89


47.

Suppose ω1 and  ω2, are two distinct cube roots of unitdifferent from 1. Then what is ω1 - ω22 equal t?

  • 3

  • 1

  •  - 1

  •  - 3


48.

Let  α and β be the roots of the equation :

x2 - 1 - 2a2x + 1 - 2a2 = 0

Under what condition does the above equation have real roots ?

  • a2 < 12

  • a2 > 12

  • a2  12

  • a2  12


Advertisement
49.

Let  α and β be the roots of the equation :

x2 - 1 - 2a2x + 1 - 2a2 = 0

Under what condition 1α2 + 1β2 < 1 ?

  • a2 < 12

  • a2 > 12

  • a2 > 1

  • a2  13, 12 only


50.

What is 1 + ω21 + ω = ?, where ω is cube root of unity

  • 1

  • ω

  • ω2

  • None of the above


Advertisement