# If (1,2),(3,4) are limiting points and x2+y2-x+ky=0 is one circle of a coaxal system then k=

1.  9

2.  -9

3.  -3

4.  3

4

-3

Explanation :
No Explanation available for this question

# The equation ax2+ay2+az2+2ux+2vy+2wz+d=0,a≠0 represent a sphere if

4

Explanation :
No Explanation available for this question

# The equation x2+y2+z2+2ux+2vy+2wz+d=0 represents a sphere if u2+v2+w2-d is

1.  Positive or zero

2.  -2

3.  Negative

4.  Zero or negative

4

Positive or zero

Explanation :
No Explanation available for this question

# Centre of the sphere (x-x1)(x-x2)+(y-y1)(y-y2)+(z-z1)(z-z2)=0

1.  [(x1+x2)/2,(y1+y2)/2,(z1+z2)/2]

2.  [(x1-x2)/2,(y1-y2)/2,(z1-z2)/2]

3.  (x2,y ,z2)

4.  (x1,y1,z1)

4

[(x1+x2)/2,(y1+y2)/2,(z1+z2)/2]

Explanation :
No Explanation available for this question

# Number of circles that can be drawn to touching all the three lines x+y-2=0,3x+4y+7=0 and 2x+2y-3=0

1.  4

2.  2

3.  1

4.  0

4

2

Explanation :
No Explanation available for this question

# The length of the direct common tangent of the circles x2+y2-4x-10y+28=0 and x2+y2+4x-6y+4=0 is

1.  16

2.  √20

3.  4

4.  2

4

4

Explanation :
No Explanation available for this question

# The length of the common chord of the circles(x-a2)+y2=a2 and x2+(y-b)2=b2 is

1.

2.  ab/(a+b)

3.  2ab/(a2+b2)

4.

4

Explanation :
No Explanation available for this question

# Order and degree of (d2y/dx2)3+(dy/dx)=ex are

1.  1,2

2.  2,3

3.  3,1

4.  1,1

4

2,3

Explanation :
No Explanation available for this question

# Order and degree of (d2y/dx2)3-(dy/dx)4+y3=cosecx are

1.  2,3

2.  1,4

3.  3,4

4.  1,2

4

2,3

Explanation :
No Explanation available for this question

1.  y1+xy=0

2.  y1=xy

3.  xdy+ydx=0

4.  xdy-ydx=0

4