Home
Class 12
MATHS
Tangent to a curve intercepts the y-axis...

Tangent to a curve intercepts the y-axis at a point `Pdot` A line perpendicular to this tangent through `P` passes through another point (1,0). The differential equation of the curve is (a) `( b ) (c) y (d)(( e ) dy)/( f )(( g ) dx)( h ) (i)-x (j) (k)(( l ) (m) (n)(( o ) dy)/( p )(( q ) dx)( r ) (s) (t))^(( u )2( v ))( w )=1( x )` (y) (b) `( z ) (aa) (bb)(( c c ) x (dd) d^(( e e )2( f f ))( g g ))/( h h )(( i i ) d (jj) x^(( k k )2( l l ))( m m ))( n n ) (oo)+( p p ) (qq)(( r r ) (ss) (tt)(( u u ) dy)/( v v )(( w w ) dx)( x x ) (yy) (zz))^(( a a a )2( b b b ))( c c c )=0( d d d )` (eee) (c) `( d ) (e) y (f)(( g ) dx)/( h )(( i ) dy)( j ) (k)+x=1( l )` (m) (d) None of these

A

`y(dy)/(dx) -x((dy)/(dx))^(2)=1`

B

`(xd^(2)y)/(dx^(2))+((dy)/(dx))^(2)=0`

C

`y(dy)/(dx)+x=1`

D

None of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to derive the differential equation of the curve based on the given conditions about the tangent and the perpendicular line. Here’s a step-by-step breakdown of the solution: ### Step 1: Define the points and the tangent Let \( P \) be the point where the tangent to the curve intersects the y-axis. Let the curve be represented by the function \( y = f(x) \). The point \( R \) on the curve where the tangent is drawn can be represented as \( (x, f(x)) \). ### Step 2: Write the equation of the tangent line The equation of the tangent line at point \( R \) can be expressed as: \[ y - f(x) = f'(x)(x - x) \] This simplifies to: \[ y = f'(x)(x - x) + f(x) \] Since the tangent intersects the y-axis at point \( P \), we can set \( x = 0 \) to find the y-intercept: \[ y = f'(x)(0 - x) + f(x) \] Thus, the y-coordinate of point \( P \) is: \[ P = (0, f(x) - f'(x)x) \] ### Step 3: Determine the slope of the perpendicular line The slope of the tangent line at point \( R \) is \( f'(x) \). Therefore, the slope of the line perpendicular to the tangent line is: \[ -\frac{1}{f'(x)} \] ### Step 4: Equation of the perpendicular line through point \( P \) The equation of the line perpendicular to the tangent through point \( P \) can be written as: \[ y - (f(x) - f'(x)x) = -\frac{1}{f'(x)}(x - 0) \] This simplifies to: \[ y = -\frac{1}{f'(x)}x + f(x) - f'(x)x \] ### Step 5: Substitute the point (1, 0) Since this line passes through the point \( (1, 0) \), we can substitute \( x = 1 \) and \( y = 0 \): \[ 0 = -\frac{1}{f'(x)}(1) + f(x) - f'(x)x \] This leads to: \[ f(x) - f'(x)x = \frac{1}{f'(x)} \] ### Step 6: Rearranging the equation Rearranging the equation gives us: \[ f(x)f'(x) - f'(x)^2x = 1 \] ### Step 7: Change variables Let \( y = f(x) \). Then, we can express the equation as: \[ y f'(x) - (f'(x))^2 x = 1 \] ### Step 8: Formulate the differential equation This can be rewritten in terms of derivatives: \[ y \frac{dy}{dx} - x \left( \frac{dy}{dx} \right)^2 = 1 \] ### Conclusion Thus, the differential equation of the curve is: \[ y \frac{dy}{dx} - x \left( \frac{dy}{dx} \right)^2 = 1 \] ### Final Answer The correct option is (a). ---

To solve the problem, we need to derive the differential equation of the curve based on the given conditions about the tangent and the perpendicular line. Here’s a step-by-step breakdown of the solution: ### Step 1: Define the points and the tangent Let \( P \) be the point where the tangent to the curve intersects the y-axis. Let the curve be represented by the function \( y = f(x) \). The point \( R \) on the curve where the tangent is drawn can be represented as \( (x, f(x)) \). ### Step 2: Write the equation of the tangent line The equation of the tangent line at point \( R \) can be expressed as: \[ ...
Promotional Banner

Topper's Solved these Questions

  • DIFFERENTIAL EQUATIONS

    CENGAGE ENGLISH|Exercise MULTIPLE CORRECT ANSWERS TYPE|17 Videos
  • DIFFERENTIAL EQUATIONS

    CENGAGE ENGLISH|Exercise Linked Comprehension types|21 Videos
  • DIFFERENTIAL EQUATIONS

    CENGAGE ENGLISH|Exercise CONCEPT APPLICATION EXERCISES 10.9|5 Videos
  • DIFFERENT PRODUCTS OF VECTORS AND THEIR GEOMETRICAL APPLICATIONS

    CENGAGE ENGLISH|Exercise Multiple correct answers type|11 Videos
  • DIFFERENTIATION

    CENGAGE ENGLISH|Exercise Archives|14 Videos
CENGAGE ENGLISH-DIFFERENTIAL EQUATIONS-SINGLE CORRECT ANSWER TYPES
  1. The solution of the differential equation x^2(dy)/(dx)cos(1/x)-ysin(1/...

    Text Solution

    |

  2. The solution of (dy)/(dx)=(x^2+y^2+1)/(2x y) satisfying y(1)=1 is give...

    Text Solution

    |

  3. The solution of the differential equation (dy)/(dx)=1/(x y[x^2siny^2+1...

    Text Solution

    |

  4. The equation of a curve passing through (2,7/2) and having gradient...

    Text Solution

    |

  5. Which of the following is not the differential equation of family of c...

    Text Solution

    |

  6. Tangent to a curve intercepts the y-axis at a point Pdot A line ...

    Text Solution

    |

  7. Orthogonal trajectories of family of the curve x^(2/3)+y^2/3=a^((2/3))...

    Text Solution

    |

  8. The curve in the first quadrant for which the normal at any point (...

    Text Solution

    |

  9. The equation of the curve which is such that the portion of the axi...

    Text Solution

    |

  10. The family of curves represented by (dy)/(dx)=(x^(2)+x+1)/(y^(2)+y+1) ...

    Text Solution

    |

  11. A normal at P(x , y) on a curve meets the x-axis at Q and N is the f...

    Text Solution

    |

  12. A curve is such that the mid-point of the portion of the tangent in...

    Text Solution

    |

  13. The normal to a curve at P(x , y) meet the x-axis at Gdot If the ...

    Text Solution

    |

  14. The x-intercept of the tangent to a curve is equal to the ordinate of ...

    Text Solution

    |

  15. The equation of a curve passing through (1,0) for which the product...

    Text Solution

    |

  16. The curve with the property that the projection of the ordinate on ...

    Text Solution

    |

  17. Spherical rain drop evaporates at a rate proportional to its surfac...

    Text Solution

    |

  18. Water is drained from a vertical cylindrical tank by opening a value a...

    Text Solution

    |

  19. The population of a country increases at a rate proportional to the...

    Text Solution

    |

  20. An object falling from rest in air is subject not only to the gravit...

    Text Solution

    |