Question Bank No: 1

1. The condition for polynomial equation ax2 + bx + c = 0 to be quadratic is

 a) a>0
 b)a<0
 c)a0
 d)a0, b0

2. The number of real solutions of the equation |x|23|x|+2 = 0 is

 a)4
 b)1
 c)3
 d)2

3. The equation x + 1/x = 2x2 has a root x = 1, therefore, it will have

 a)No other root
 b)one more root only
 c)two more roots only
 d)Another root as x = -1

4. If a, b are non real roots of ax2 + bx + c = 0 (a, b, c ϵ R), then

 a)a = b
 b)ab = 1
 c)a = ¯b
 d)a¯b = 1

5. The roots of (x – a) (x – b) = abx2 are always

 a)Real
 b)depends upon a
 c)depends upon b
 d)Depends upon a and b

6. The equation (b - c) x2 + (c – a) x + (a –b) = 0 has

 a)Equal roots
 b)irrational roots
 c)rational roots
 d)None of these

7. Both the roots of the equation ax2 + bx + c = 0, a 0, are zero if

 a)b = 0, c = 0
 b)b = 0, c 0
 c)b 0, c = 0
 d)b 0, c 0

8. If ax2 = bx + c = 0 is satisfied by every value of x, then

 a) b = 0, c = 0
 b)c = 0
 c)b = 0
 d)a = b = c = 0

9. Roots of x2 + k = 0, k < 0 are

 a)Complex conjugates
 b)real and distinct
 c)real and equal
 d)rational

10. If the roots of ax2+ b = 0 are real and distinct then

 a)ab > 0
 b)a = 0
 c)ab < 0
 d)a > 0, b > 0

11. If the product of the roots of the equation mx2+ 6x + (2m – 1) = 0 is -1, then the value of m

 a)1
 b)-1
 c)1/3
 d)-1/3

12. If a > 0, b > 0, c > 0, then the roots of the equation ax2 + bx + c = 0 are

 a)Real and negative
 b)non-real with negative real parts
 c)Real and positive
 d)nothing can be said

13. If a, b are odd integers, then the roots of the equation 2ax2 + (2a + b)x + b = 0 are

 a)Rational
 b)irrational
 c)non real
 d)equal

14. The quadratic equation 8 sec2θ – 6 secθ + 1 = 0 has

 a)Infinitely many roots
 b)exactly two roots
 c)exactly four roots
 d)no roots

15. If one root of the equation ax2+ bx + c = 0, a 0, be reciprocal of the other, then

 a)b = c
 b)a = c
 c)a = 0
 d)b = 0

16. If the roots of ax2 + bx + c = 0 are equal in magnitude but opposite in sign, then

 a)a = 0
 b)b = 0
 c)c = 0
 d)none of these

17. If a, b are the roots of the equation x2 - 2x + 2 = 0, then the value of a2 + b2 is

 a)2
 b)0
 c)1
 d)4

18. If a, b are the roots of ax2 + bx + c = 0, the roots of cx2 + bx + a = 0 are

 a)– a, -b
 b)a, 1/b
 c)b, 1/a
 d)1/a, 1/b

19. The number of real roots of the equation 22x2 - 7x + 5 = 1 is

 a)0
 b)1
 c)2
 d)4

20. The roots of the equation x2 + ax + b = 0 where a = 2b and b > 3 are

 a)equal
 b)unequal
 c)imaginary
 d)none of these

21. If x = a is one of the factors of the polynomial ax2 + bx + c, then one of the roots of ax2 + bx + c = 0 is

 a)a
 b)b
 c)c
 d)none of these

22. If one root of the equation x2 + px + 12 = 0 is 4 while the equation x2 + px + q = 0 has equal roots, the value of q is

 a)49/4
 b)4/49
 c)4
 d)none of these

23. If the root of equation axa + bxb =1 are eqal in magnitude and oppositing sign then,

 a) a – b = 0
 b)a + b = 1
 c)a – b = 1
 d)a + b = 0

24. The numerical difference of the roots of x2 - 7x – 9 = 0 is

 a)5
 b)25
 c)97
 d)85

25. The value of p and q (p 0, q 0) for which p, q are the roots of the equation x2+ px + q = 0 are

 a)p = 1, q = 2
 b)p = -1, q = 2
 c)p = -1, q = -2
 d)p = 1, q = -2

26. If a + b + c = 0, a 0, a, b, c ϵ Q, then both the roots of the equation ax2 + bx + c = 0 are

 a)rational
 b)irrational
 c)non-real
 d)zero

27. If the roots of the equation 12x2 + mx + 5 = 0 are in the ratio 3:2, then m equals

 a)12
 b)512
 c)510
 d)51210

28. If a, b, c are positive real numbers, then the number of real roots of the equation

28. ax2+b|x|+c= 0 is

 a)2
 b)4
 c)0
 d)1

29. The values of x which satisfy both the equations x2-1≤ 0 and x2 - x – 2 ≥ 0 lies in

 a)( -1, 2)
 b)(-1, 1)
 c)(1, 2)
 d){ -1 }

30. Ram and sham solved a quadratic equation. In solving it Ram made a mistake in the constant term only and got the roots as 8 and 2, while sham made a mistake in the co-efficient of x only and obtained -9 and -1 as roots. The correct roots of the equation are

 a)8, -1
 b)-9, 2
 c)-8, -2
 d)9, 1

31. If a non-zero root of the equation x2 + 2x + 3λ = 0 and 2x2 + 3x + 5λ = 0 is common, then the value of λ will be

 a)2
 b)1
 c)-1
 d)0

32. If a and b are the roots of x2 + px + q = 0 and a4, b4 are the roots of x²x2 - rx + s = 0, then the equation x2 - 4 qx + 2q² - r = 0 has always

 a)two real roots
 b)two positive roots
 c)two negative roots
 d)one

33. If the roots of x2 - bx + c = 0 are two consecutive integers, then b2 - 4c is

 a)0
 b)1
 c)2
 d)None of these

34. Let the equation ax2 - bx + c = 0 have distinct real roots both lying in the open interval (0, 1) where a, b, c are given to be positive integers. Then the value of the ordered triplet (a, b, c) can be

 a)(5, 3, 1)
 b)(4, 3, 2)
 c)(5, 5, 1)
 d)(6, 4, 1)

35. The condition that x3 - px2 + qx – r = 0 may have two of its roots equal to each other but of opposite signs is

 a)r = pq
 b) r = 2p3 + pq
 c)r = p2q
 d)none of these

36. All the integral values of x for which 7x – 3 >(x+1)2> x + 3 lie in the interval

 a)[1,2]
 b)[2,3]
 c)[3,4]
 d)none of these

37. The solution set of the equation |5x3| = -1 is

 a){ 0 }
 b)φ
 c){ 35 }
 d)none of these

38. if x, y ϵ R, xy rational, y irrational and x rational, then

 a)x > 0
 b)x < 0
 c)x = 0
 d)x 0

39. If x ϵ R, then x2 + x + 2

 a)is negative
 b)is positive
 c)ϵ[74,]
 d)ϵ [ 1, ]

40. If x and y are real numbers such that x > y and |x|< |y|, then;

 a)x < 0
 b)x > 0
 c)y > 0
 d)y < 0

41. If 2 – 3x – 2 x2 0, then,

 a)x - 2
 b)x 12
 c)x -2
 d)– 2 x 12

42. Irrational numbers are;

 a)irrational decimals
 b)non-terminating, recurring decimals
 c)non-terminating, non recurring decimals
 d)none of these

43. If x be a positive real, then the least value of x + 1/x is

 a)2
 b)4
 c)11
 d)1

44. If x is a non-zero rational number and xy is irrational, then y must be

 a)a rational number
 b)an irrational number
 c)non-zero
 d)an integer

45. If a,b are the roots of x2 - 2x + 4 = 0, then a/b is equal to

 a)12 (1 - 3 i)
 b)12 (1 + 3)
 c) 1/2 (-1 ± 3 i)
 d)3i2