# A bag contains 5 black balls. 4 white balls and 3 red balls. If a ball is selected at random, the probability that it is a black or a red ball is

1.  1/3

2.  1/4

3.  5/12

4.  2/3

4

2/3

Explanation :
No Explanation available for this question

# A line is at a constant distance c from the origin and meets the co-ordinate axes in A and B. The locus of the centre of the circle patting through O, A, B is

1.  x2 + y2 = c2

2.  x2 + y2 = 2c2

3.  x2 + y2 = 3c2

4.  x2 + y2 = 4c2

4

x2 + y2 = 4c2

Explanation :
No Explanation available for this question

# The pole of the straight line x+4y = 4 With respect to the ellipse x2 + 4y2 = 4 is

1.  (1, 1)

2.  (1, 4)

3.  (4, 1)

4.  (4, 4)

4

(1, 1)

Explanation :
No Explanation available for this question

# Locus of the poles of focal chord of a parabola is

1.  The axis

2.  A focal chord

3.  The directrix

4.  The tangent at the vertex

4

The directrix

Explanation :
No Explanation available for this question

# The quadratic equation whose roots are l and m, where

1.  x2 + 5x + 6 = 0

2.  x2 - 5x + 6 = 0

3.  x2 - 5x - 6 = 0

4.  x2 + 5x - 6 = 0

4

x2 - 5x + 6 = 0

Explanation :
No Explanation available for this question

1.

2.

3.

4.

4 Explanation :
No Explanation available for this question

# The value of θ (0 < θ < 3600) satisfying cosecθ + 2 = 0 are

1.  2100, 3000

2.  2100, 2400

3.  2100, 3300

4.  2400, 3000

4

2100, 3000

Explanation :
No Explanation available for this question

# If x = y cos (2π/3) = z cos (4π/3), then xy + yz + zx is equal to

1.  -1

2.  0

3.  1

4.  2

4

-1

Explanation :
No Explanation available for this question

# If sinα = sinβ and cosα = cosβ, then

1.  sin ((α-β) / 2) = 0

2.  cos ((α+β) / 2) = 0

3.  sin ((α+β) / 2) = 0

4.  cos ((α-β) / 2) = 0

4

sin ((α-β) / 2) = 0

Explanation :
No Explanation available for this question

# Consider the function f(x)=x sin(1/x),x≠0 and f(0) =0,then

1.  it is continuous for all real values of x

2.  it is discontinuous everywhere

3.  f(x) exists and discontinuous at x=π/2

4.  none of these

4