The differential equation of the family of circles touching Y-axi

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

11.

If A = 22- 32, B = 0- 110, then (B- 1A- 1)- 1 is equal to

  • 2- 223

  • 22- 23

  • 2- 322

  • 1- 1- 23


12.

If matrix A = 1243 such that AX = ϕ,then X is equal to

  • 15132- 1

  • 15424- 1

  • 15- 324- 1

  • 15- 12- 14


Advertisement

13.

The differential equation of the family of circles touching Y-axis at the origin is

  • x2 + y2dydx - 2xy = 0

  • x2 - y2 + 2xydydx = 0

  • x2 - y2dydx - 2xy = 0

  • x2 + y2dydx + 2xy = 0


B.

x2 - y2 + 2xydydx = 0

Let centre of circle on X-axis be (h, 0),

The radius of circle will be h.

 The equation of circle having centre (h, 0) and radius h is

     x - h2 + y - 02 = h2 x2 + h2 - 2hx + y2 = h2          x2 - 2hx + y2 = 0     ...(i)On differentiating both sides w.r.tx, we get2x - 2h +2ydydx = 0                     h = x + ydydxOn putting h = x + ydydx in Eq. (i), we getx2 - 2x + ydydxx + y2 = 0 - x2 + y2 - 2xydydx = 0    x2 - y2 + 2xydydx = 0


Advertisement
14.

Direction cosines of the line x + 22 = 2y - 53, z = - 1 are

  • 45, 35, 0

  • 35, 45, 15

  • - 35, 45, 0

  • 45, - 25, 15


Advertisement
15.

18 + 2x - x2dx is equal to

  • 13sin-1x - 13 + c

  • sin-1x + 13 + c

  • 13sin-1x + 13 + c

  • sin-1x - 13 + c


16.

If random variable waiting time in minutes for bus and probability density function of x is given by

fx = 15, 0  x  50  , otherwise

then probability of waiting time not more than 4 minutes is equal to

  • 0.3

  • 0.8

  • 0.2

  • 0.5


17.

4ex - 252ex - 5dx = Ax + Blog2ex - 5 + c, then

  • A = 5 and B = 3

  • A = 5 and B = - 3

  • A = - 5 and B = 3

  • A = - 5 and B = - 3


18.

- π2π2log2 - sinx2 + sinxdx is equal to

  • 1

  • 3

  • 2

  • 0


Advertisement
19.

x2 + 2ax + tan-1xx2 + 1dx is equal to

  • loga . ax + tan-1x + c

  • x + tan-1xlogloga + c

  • ax + tan-1xloga + c

  • logax + tan-1x + c


20.

The degree and order of the differential equation 1 + dydx373 = 7d2ydx2 respectively are

  • 3 and 7

  • 3 and 2

  • 7 and 3

  • 2 and 3


Advertisement