Home
Class 12
MATHS
Let the trajectories cut the crve of giv...

Let the trajectories cut the crve of given family at an angle `alpha` where `tna alpha = k`.
The slope `(dy)/(dx) = tan Psi` (of the tangent to a member of the family and the slope `(dy_(T))/(dx) = tan Phi` to the isogonal trajectory are connected by the relationship

`tan phi = tan (Psi - alpha) = (tan Psi - tan alpha)/(1+ tan alpha tan Psi)`
i.e., `(dy)/(dx) = (((dy_(T))/(dx))-k)/(k(dy_(T))/(dx)+1)`
Substituting this expression into equation, (l') and dropping the subscript T, we obtain the differential equation of isogonal trajectories.
The isogonal trajectories of a family of straight lines y = c, that cuts the given family at angle `alpha`, the tangent of which is k, is

A

(a)y = kx

B

(b)`y = k tan alpha x`

C

(c)`y = k cot 2 x`

D

(d)y = cx

Text Solution

Verified by Experts

The correct Answer is:
A
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • DIFFERENTIAL EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise Assignment Section - E (Assertion - Reason Type Questions)|10 Videos
  • DIFFERENTIAL EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise Assignment Section - F (Matrix-Match Type Questions)|2 Videos
  • DIFFERENTIAL EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise Assignment Section - C (Objective Type Questions) (Multiple than one options are correct)|17 Videos
  • DETERMINANTS

    AAKASH INSTITUTE ENGLISH|Exercise SECTION - J|12 Videos
  • INTEGRALS

    AAKASH INSTITUTE ENGLISH|Exercise Try yourself|50 Videos

Similar Questions

Explore conceptually related problems

If tan 2theta= sec 2 alpha , prove that sin 2theta=(1-tan^4 alpha)/(1+tan^4 alpha)

If sin (theta + alpha ) = cos ( theta + alpha), prove that tan theta =(1- tan alpha )/(1 + tan alpha )

(1+tan alpha tan beta)^2 + (tan alpha - tan beta)^2 =

write tan 8 alpha in temrs of tan 4 alpha .

Simplify be reducing to a single term : (tan alpha - tan ( alpha - beta))/(1 + tan alpha tan ( alpha - beta))

tan alpha + 2 tan 2alpha + 4 tan 4 alpha + 8 cot 8 alpha =

If tan theta=(sin alpha- cos alpha)/(sin alpha+cos alpha) , then:

Prove that cot alpha - tan alpha =2 cot 2 alpha.

Prove: (2)/( cot alpha tan 2 alpha ) = 1 - tan ^(2) alpha.

Equation of normal to y=tan x at (alpha, tan alpha)