If one root of ax2 + bx + c = 0 is twice the other root, then fr

Subject

Mathematics

Class

JEE Class 12

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

1.

If A(z1), B(z2), C(z3) and P(z) represent complex numbers such that z1 - z = z2 - z = z3 - z, then, A, B, C lies on

  • a straight line

  • a circle

  • a parabola

  • an ellipse


2.

If the complex numbers z, z, and origin form vertices of an equilateral triangle, then the value of z12 + z22 will be

  • z1z2

  • z1 + z2

  • 2z1z2

  • z1 - z2


3.

Three numbers form an increasing GP. If the middle term is doubled, then the new numbers are in AP. The commonratio of the GP will be

  • 2 - 3

  • 2 ± 3

  • 32

  • 2 + 3


4.

If the equations ax2 + 2cx + b = 0 and ax2 + 2bx + c = 0 b  c have a common root, then the value of a + 4b + 4c will be

  • 2

  • 1

  • - 1

  • Non eof these


Advertisement
Advertisement

5.

If one root of ax2 + bx + c = 0 is twice the other root, then

  • b2 = 9ac

  • 2b2 = 9ac

  • 2b2 = ac

  • b2 = ac


B.

2b2 = 9ac

Let the roots ofthe equation ax2 + bx + c = 0 be α, then other root is 2α.

 α + 2α = - ba  3α = - ba     ...iand α . 2α = ca  α2 = c2a            ...ii From Eq. (i),     9c2a = b2a2  2b2 = 9ac


Advertisement
6.

The number of ways of distributing 8 distinct toys among 5 children will be

  • 58

  • 85

  • P58

  • 40


7.

The value of C1 - 2 . C2 + 3 . C3 - 4 . C4 + ... where CrCrn will be

  • - 1

  • 1

  • 0

  • None of these


8.

In a ABC, if tanA2 = 56 and tanC2 = 25, then the sides a, b, c are in

  • AP

  • GP

  • HP

  • None of these


Advertisement
9.

The value of cosπ5cos2π5cos4π5cos8π5 will be

  • 116

  • - 116

  • 0

  • 12


10.

The distance between the lines 3x + 4y = 9 and 6x + 8y = 15 will be

  • 32

  • 38

  • 310

  • 6


Advertisement