Maths-
General
Easy

Question

If the area of the triangle, included between the axes and any tangent to the curve x y to the power of n end exponent equals a to the power of n plus 1 end exponent is constant, then the value of n is

  1. negative 1  
  2. negative 2  
  3. 1  
  4. 2  

The correct answer is: 1


    We have,
    x y to the power of n end exponent equals a to the power of n plus 1 end exponent rightwards double arrow y to the power of n end exponent plus n blank x y to the power of n minus 1 end exponent fraction numerator d y over denominator d x end fraction equals 0 rightwards double arrow fraction numerator d y over denominator d x end fraction equals negative fraction numerator y over denominator n x end fraction

    Let open parentheses x subscript 1 end subscript comma blank y subscript 1 end subscript close parentheses be a point on x blank y to the power of n end exponent equals a to the power of n plus 1 end exponent. The equation of the tangent at left parenthesis x subscript 1 end subscript comma blank y subscript 1 end subscript right parenthesis is

    y equals y subscript 1 end subscript equals negative fraction numerator y subscript 1 end subscript over denominator n x subscript 1 end subscript end fraction open parentheses x minus x subscript 1 end subscript close parentheses

    This meets with the coordinate axes at A open parentheses open parentheses n plus 1 close parentheses x subscript 1 end subscript comma blank 0 close parentheses and B open parentheses 0 comma fraction numerator open parentheses n plus 1 close parentheses y subscript 1 end subscript over denominator n end fraction close parentheses

    therefore Area of increment O A B equals fraction numerator 1 over denominator 2 end fraction open parentheses n plus 1 close parentheses x subscript 1 end subscript bullet open parentheses fraction numerator n plus 1 over denominator n end fraction close parentheses y subscript 1 end subscript

    rightwards double arrow Area of increment O A B equals fraction numerator 1 over denominator 2 end fraction fraction numerator open parentheses n plus 1 close parentheses to the power of 2 end exponent over denominator n end fraction x subscript 1 end subscript y subscript 1 end subscript …(i)

    Since left parenthesis x subscript 1 end subscript comma blank y subscript 1 end subscript right parenthesis lies on x y to the power of n end exponent equals a to the power of n plus 1 end exponent

    therefore x subscript 1 end subscript y subscript 1 end subscript superscript n end superscript equals a to the power of n plus 1 end exponent open parentheses x subscript 1 end subscript comma blank y subscript 1 end subscript close parentheses rightwards double arrow x subscript 1 end subscript equals fraction numerator a to the power of n plus 1 end exponent over denominator y subscript 1 end subscript superscript n end superscript end fraction

    Putting the value of x subscript 1 end subscript in (i), we get

    Area of increment O A B equals fraction numerator 1 over denominator 2 end fraction fraction numerator open parentheses n plus 1 close parentheses to the power of 2 end exponent over denominator n end fraction a to the power of n plus 1 end exponent y subscript 1 end subscript superscript negative n plus 1 end superscript

    This will be a constant, if n equals 1

    Related Questions to study

    General
    Maths-

    The fixed point P on the curve y equals x to the power of 2 end exponent minus 4 x plus 5 such that the tangent at P is perpendicular to the line x plus 2 y minus 7 equals 0 is given by

    The fixed point P on the curve y equals x to the power of 2 end exponent minus 4 x plus 5 such that the tangent at P is perpendicular to the line x plus 2 y minus 7 equals 0 is given by

    Maths-General
    General
    Maths-

    The function f open parentheses x close parentheses equals x to the power of 3 end exponent plus a x to the power of 2 end exponent plus b x plus c comma a to the power of 2 end exponent less or equal than 3 b blank h a s

    The function f open parentheses x close parentheses equals x to the power of 3 end exponent plus a x to the power of 2 end exponent plus b x plus c comma a to the power of 2 end exponent less or equal than 3 b blank h a s

    Maths-General
    General
    Maths-

    How many real solutions does the equation x to the power of 7 end exponent plus 14 x to the power of 5 end exponent plus 16 x to the power of 3 end exponent plus 30 x minus 560 equals 0 have?

    How many real solutions does the equation x to the power of 7 end exponent plus 14 x to the power of 5 end exponent plus 16 x to the power of 3 end exponent plus 30 x minus 560 equals 0 have?

    Maths-General
    parallel
    General
    Maths-

    If y equals x to the power of n end exponent comma then the ratio of relative errors in y and x is

    If y equals x to the power of n end exponent comma then the ratio of relative errors in y and x is

    Maths-General
    General
    Maths-

    If a and b are positive numbers such that a greater than b comma then the minimum value of a   sec invisible function application blank theta minus b tan invisible function application theta open parentheses 0 less than theta less than fraction numerator pi over denominator 2 end fraction close parentheses is

    If a and b are positive numbers such that a greater than b comma then the minimum value of a   sec invisible function application blank theta minus b tan invisible function application theta open parentheses 0 less than theta less than fraction numerator pi over denominator 2 end fraction close parentheses is

    Maths-General
    General
    Maths-

    The side of an equilateral triangle is ´ a ´ units and is increasing at the rate of lambda blank u n i t s divided by s e c. The rate of increase of its area is

    The side of an equilateral triangle is ´ a ´ units and is increasing at the rate of lambda blank u n i t s divided by s e c. The rate of increase of its area is

    Maths-General
    parallel
    General
    Maths-

    In how many ways four men and three women may sit around a round table if all the women are together.

    In how many ways four men and three women may sit around a round table if all the women are together.

    Maths-General
    General
    Maths-

    In how many ways 5 persons can sit at a round table, if two of the persons does not sit together.

    In how many ways 5 persons can sit at a round table, if two of the persons does not sit together.

    Maths-General
    General
    Maths-

    The function f open parentheses x close parentheses equals fraction numerator x over denominator 2 end fraction plus fraction numerator 2 over denominator x end fraction has local minimum at

    The function f open parentheses x close parentheses equals fraction numerator x over denominator 2 end fraction plus fraction numerator 2 over denominator x end fraction has local minimum at

    Maths-General
    parallel
    General
    Maths-

    On which of the following intervals is the function f open parentheses x close parentheses equals 2 blank x to the power of 2 end exponent minus log invisible function application open vertical bar x close vertical bar comma x not equal to 0 increasing?

    On which of the following intervals is the function f open parentheses x close parentheses equals 2 blank x to the power of 2 end exponent minus log invisible function application open vertical bar x close vertical bar comma x not equal to 0 increasing?

    Maths-General
    General
    Physics-

    A conducting circular loop is placed in a uniform magnetic field 0.04 blank T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2 blank m m divided by s. The induced e m f in the loop when the radius is 2 blank c m is

    A conducting circular loop is placed in a uniform magnetic field 0.04 blank T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2 blank m m divided by s. The induced e m f in the loop when the radius is 2 blank c m is

    Physics-General
    General
    Physics-

    198.The transformation ratio in the step-up transformer is

    198.The transformation ratio in the step-up transformer is

    Physics-General
    parallel
    General
    Physics-

    Two coils A and B having turns 300 and 600 respectively are placed near each other, on passing a current of 3.0 blank a m p e r e in A, the flux linked with A is 1.2 cross times 10 to the power of negative 4 end exponent blank w e b e r and with B it is 9.0 cross times 10 to the power of negative 5 end exponent w e b e r. The mutual inductance of the system is

    Two coils A and B having turns 300 and 600 respectively are placed near each other, on passing a current of 3.0 blank a m p e r e in A, the flux linked with A is 1.2 cross times 10 to the power of negative 4 end exponent blank w e b e r and with B it is 9.0 cross times 10 to the power of negative 5 end exponent w e b e r. The mutual inductance of the system is

    Physics-General
    General
    Physics-

    The magnetic flux across a loop of resistance 10 capital omega is given by ϕ equals 5 t to the power of 2 end exponent minus 4 t plus 1 blank w e b e r. How much current is induced in the loop after 0.2 sec

    The magnetic flux across a loop of resistance 10 capital omega is given by ϕ equals 5 t to the power of 2 end exponent minus 4 t plus 1 blank w e b e r. How much current is induced in the loop after 0.2 sec

    Physics-General
    General
    Physics-

    A conducting square loop of side L and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. A magnetic induction B constant in time and space, pointing perpendicular and into the plane of the loop exists everywhere with part of the loop outside the field, as shown in figure. The induced emf is

    A conducting square loop of side L and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. A magnetic induction B constant in time and space, pointing perpendicular and into the plane of the loop exists everywhere with part of the loop outside the field, as shown in figure. The induced emf is
    Physics-General

    parallel

    card img

    With Turito Academy.

    card img

    With Turito Foundation.

    card img

    Get an Expert Advice From Turito.

    Turito Academy

    card img

    With Turito Academy.

    Test Prep

    card img

    With Turito Foundation.