Home
Class 12
MATHS
Let a solution y=y(x) of the differenti...

Let a solution y=y(x) of the differential equation `xsqrt(x^(2)-1) dy-ysqrt(y^(2)-1)dx=0` satisfy `y(2)=(2) /(sqrt3)`
Statement I `y(x)=sec(sec^(-1)x-(pi)/(6))`
Statement II y(x) is given by `(1)/(y) =(2sqrt3)/(x)-sqrt(1-(1)/(x^(2)))`

A

Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.

B

Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.

C

Statement-1 is True, Statement-2 is False.

D

Statement-1 is False, Statement-2 is True.

Text Solution

Verified by Experts

The correct Answer is:
C

We have,
`xsqrt(x^(2)-1)dy=ysqrt(y^(2)-1)dx`
`rArr" "(1)/(ysqrt(y^(2)-1))dy=(1)/(x sqrt(x^(2)-1))dx`
`rArr" "int(1)/(ysqrt(y^(2)-1))dy=int(1)/(xsqrt(x^(2)-1))dx`
`rArr" "sec^(-1)y=sec^(-1)x+C`
It is given that `y=(2)/(sqrt3)` when x = 2
`therefore" "sec^(-1).(2)/(sqrt3)=sec^(-1)2+CrArr(pi)/(6)=(pi)/(3)+CrArrC=-(pi)/(6)`
Putting `C=-(pi)/(6)` in (i), we get
`sec^(-1)y=sec^(-1)x-(pi)/(6)" ...(ii)"`
`rArr" "y=sec(sec^(-1)x-(pi)/(6))`
so, statement-1 is true.
From (ii), we have
`cos^(-1)((1)/(y))=cos^(-1)((1)/(x))-(pi)/(6)`
`rArr" "(1)/(y)=cos{cos^(-1)((1)/(x))-(pi)/(6)}`
`rArr" "(1)/(y)=cos{cos^(-1)((1)/(x))}cos((pi)/(6))+sin(cos^(-1).(1)/(x))sin(pi)/(6)`
`rArr" "(1)/(y)=(sqrt3)/(2x)+(1)/(2)sqrt(1-(1)/(x^(2)))`
So, statement-2 is false.
Promotional Banner

Topper's Solved these Questions

  • DIFFERENTIAL EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|74 Videos
  • DIFFERENTIAL EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|30 Videos
  • DIFFERENTIAL EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section I - Solved Mcqs|48 Videos
  • DERIVATIVE AS A RATE MEASURER

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|26 Videos
  • DIFFERENTIALS, ERRORS AND APPROXIMATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|17 Videos

Similar Questions

Explore conceptually related problems

Let a solution y = y(x) of the differential equation xsqrt(x^2-1) dy - y sqrt(y^2-1) dx=0 , satisfy y(2)= 2/sqrt 3

Let a solution y=y(x) of the differential equation xsqrt(x^2-1)dy-ysqrt(y^2-1)dx=0 satisfy y(2)=2/sqrt(3) Statement-1: y(x)=sec(sec^-1x-pi/6) Statement-2: y(x) is given by 1/y=(2sqrt(3))/x-sqrt(1-1/x^2) (A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1. (C) Statement-1 is True, Statement-2 is False. (D) Statement-1 is False, Statement-2 is True.

Find the solution of the differential equation x\ sqrt(1+y^2)dx+y\ sqrt(1+x^2)dy=0.

The general solution of the differential equation sqrt(1-x^(2)y^(2)) dx = y dx + x dy is

The solution of the differential equation x^3(dy)/(dx)=y^3+y^2sqrt(y^2-x^2) is :

The solution of the differential equation {1+xsqrt((x^2+y^2))}dx+{sqrt((x^2+y^2))-1}ydy=0 is equal to

The solution of the differential equation (x)/(x^(2)+y^(2))dy = ((y)/(x^(2)+y^(2))-1)dx , is

The general solution of the differential equation (2x-y+1)dx+(2y-x+1)dy=0 is -

If y(x) is a solution of differential equation sqrt(1-x^2) dy/dx + sqrt(1-y^2) = 0 such that y(1/2) = sqrt3/2 , then

The solution of the differential equation {1/x-y^(2)/(x-y)^(2)}dx+{x^(2)/(x-y)^(2)-1/y}dy=0 is