Maths-
General
Easy

Question

Let f left parenthesis x right parenthesis equals stack l i m with n rightwards arrow infinity below left square bracket fraction numerator n to the power of n left parenthesis x plus n right parenthesis left parenthesis x plus n over 2 right parenthesis..... left parenthesis x plus n over n right parenthesis over denominator n factorial left parenthesis x squared plus n squared right parenthesis left parenthesis x squared plus n squared over 4 right parenthesis times left parenthesis x squared plus n squared over n squared right parenthesis end fraction right square bracket to the power of x divided by n end exponent, for all x greater than 0 Then

  1. f left parenthesis fraction numerator 1 over denominator 2 end fraction right parenthesis greater or equal than f left parenthesis 1 right parenthesis    
  2. f left parenthesis fraction numerator 1 over denominator 3 end fraction right parenthesis less or equal than f left parenthesis fraction numerator 2 over denominator 3 end fraction right parenthesis    
  3. f to the power of ' end exponent left parenthesis 2 right parenthesis less or equal than 0(2)0'/>    
  4. fraction numerator f to the power of ' end exponent left parenthesis 3 right parenthesis over denominator f left parenthesis 3 right parenthesis end fraction greater or equal than fraction numerator f to the power of ' end exponent left parenthesis 2 right parenthesis over denominator f left parenthesis 2 right parenthesis end fraction(3)f(3)f'(2)f(2)'/>    

The correct answer is: f to the power of ´ end exponent left parenthesis 2 right parenthesis less or equal than 0


    The given function is
    f left parenthesis x right parenthesis equals stack l i m with n rightwards arrow infinity below left square bracket fraction numerator n to the power of n end exponent left parenthesis x plus n right parenthesis left parenthesis x plus n divided by 2 right parenthesis times. times. times. left parenthesis x plus n divided by n right parenthesis over denominator n factorial left parenthesis x to the power of 2 end exponent plus n to the power of 2 end exponent right parenthesis left parenthesis x to the power of 2 end exponent plus n to the power of 2 end exponent divided by 4 right parenthesis left parenthesis x to the power of 2 end exponent plus n to the power of 2 end exponent divided by n to the power of 2 end exponent right parenthesis end fraction right square bracket to the power of x divided by n end exponent for all x greater than 0 rightwards double arrow f left parenthesis x right parenthesis equals stack l i m with n rightwards arrow infinity below left square bracket fraction numerator n to the power of n end exponent n to the power of n end exponent left parenthesis 1 plus fraction numerator chi over denominator n end fraction right parenthesis left parenthesis 1 plus fraction numerator 2 x over denominator n end fraction right parenthesis. times. times. times left parenthesis 1 plus fraction numerator n x over denominator n end fraction right parenthesis over denominator n factorial n factorial left parenthesis 1 plus fraction numerator chi to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis left parenthesis 1 plus fraction numerator 4 x to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis left parenthesis 1 plus fraction numerator n to the power of 2 end exponent x to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis end fraction cross times fraction numerator left parenthesis n factorial right parenthesis to the power of 2 end exponent over denominator left parenthesis n to the power of 2 end exponent right parenthesis to the power of n end exponent end fraction right square bracket to the power of chi divided by n end exponent f left parenthesis x right parenthesis equals stack l i m with n rightwards arrow infinity below left square bracket fraction numerator left parenthesis 1 plus fraction numerator chi over denominator n end fraction right parenthesis left parenthesis 1 plus fraction numerator 2 x over denominator n end fraction right parenthesis times. times. times. left parenthesis 1 plus fraction numerator n x over denominator n end fraction right parenthesis over denominator left parenthesis 1 plus fraction numerator chi to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis left parenthesis 1 plus fraction numerator 4 x to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis left parenthesis 1 plus fraction numerator n to the power of 2 end exponent x to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction right parenthesis end fraction right square bracket to the power of x divided by n end exponent f left parenthesis x right parenthesis equals x subscript n rightwards arrow infinity end subscript vertical line i m left square bracket not stretchy sum subscript r equals 1 end subscript superscript n end superscript fraction numerator 1 over denominator n end fraction lln left square bracket fraction numerator 1 plus fraction numerator r x over denominator n end fraction over denominator 1 plus fraction numerator r to the power of 2 end exponent x to the power of 2 end exponent over denominator n to the power of 2 end exponent end fraction end fraction 1 right square bracket
    In f left parenthesis x right parenthesis equals x not stretchy integral subscript 0 end subscript superscript 1 end superscript I n left parenthesis fraction numerator 1 plus x gamma over denominator 1 plus x to the power of 2 end exponent gamma to the power of 2 end exponent end fraction right parenthesis d gamma
    Substitutingx gamma equals ‡, we g e t rightwards double arrow d gamma equals fraction numerator d r over denominator chi end fraction.Therefore,
    In f left parenthesis x right parenthesis equals fraction numerator chi over denominator chi end fraction not stretchy integral subscript 0 end subscript superscript chi end superscript vertical line n left parenthesis fraction numerator 1 plus ‡ over denominator 1 plus ‡ to the power of 2 end exponent end fraction right parenthesis d ‡ equals not stretchy integral subscript 0 end subscript superscript chi end superscript vertical line n left parenthesis fraction numerator 1 plus ‡ over denominator 1 plus ‡ to the power of 2 end exponent end fraction right parenthesis d ‡
    Applying Newton‐Leibniz rule, we get
    fraction numerator f to the power of ´ end exponent left parenthesis x right parenthesis over denominator f left parenthesis x right parenthesis end fraction equals vertical line n left parenthesis fraction numerator 1 plus x over denominator 1 plus x to the power of 2 end exponent end fraction right parenthesis equals f to the power of ´ end exponent left parenthesis x right parenthesis equals f left parenthesis x right parenthesis vertical line n left parenthesis fraction numerator 1 plus x over denominator 1 plus x to the power of 2 end exponent end fraction right parenthesis
    lt is obvious that f left parenthesis x right parenthesis greater than 0 for all x greater than 0.
    For x equals 2 colon fraction numerator f to the power of ´ end exponent left parenthesis 2 right parenthesis over denominator f left parenthesis 2 right parenthesis end fraction equals vertical line n left parenthesis fraction numerator 3 over denominator 5 end fraction right parenthesis less than 0 equals f to the power of ´ end exponent left parenthesis 2 right parenthesis less or equal than 0
    Hence, option (C) is correct.

    Related Questions to study

    General
    Maths-

    Let f left parenthesis x right parenthesis equals left curly bracket to the power of x squared vertical line blank cos blank pi over chi vertical line end exponent right curly bracket 0 comma x equals 0 x not equal to 0 chi element of R Then f is

    Let f left parenthesis x right parenthesis equals left curly bracket to the power of x squared vertical line blank cos blank pi over chi vertical line end exponent right curly bracket 0 comma x equals 0 x not equal to 0 chi element of R Then f is

    Maths-General
    General
    Physics-

    The ratio of speed of sound in nitrogen and helium gas at 300 K is

    The ratio of speed of sound in nitrogen and helium gas at 300 K is

    Physics-General
    General
    Physics-

    If V subscript m end subscript is the velocity of sound in moist air, V subscript d end subscriptis the velocity of sound in dry air, under identical conditions of pressure and temperature

    If V subscript m end subscript is the velocity of sound in moist air, V subscript d end subscriptis the velocity of sound in dry air, under identical conditions of pressure and temperature

    Physics-General
    parallel
    General
    Maths-

    lf the function f left parenthesis x right parenthesis equals left curly bracket fraction numerator square root of 2 plus blank c o s blank x end root minus 1 over denominator k comma left parenthesis pi minus x right parenthesis squared end fraction comma x not equal to pi right curly bracket is continuous at x equals pi, then k equals

    lf the function f left parenthesis x right parenthesis equals left curly bracket fraction numerator square root of 2 plus blank c o s blank x end root minus 1 over denominator k comma left parenthesis pi minus x right parenthesis squared end fraction comma x not equal to pi right curly bracket is continuous at x equals pi, then k equals

    Maths-General
    General
    Maths-

    If capital delta(x) = open vertical bar table row cell e to the power of x end cell cell s i n invisible function application 2 x end cell cell t a n invisible function application x squared end cell row cell invisible function application left parenthesis 1 plus x right parenthesis end cell cell c o s invisible function application x end cell cell s i n invisible function application x end cell row cell c o s invisible function application x squared end cell cell e to the power of x minus 1 end cell cell s i n invisible function application x squared end cell end table close vertical bar= A + Bx + Cx2, then B is equal to

    If capital delta(x) = open vertical bar table row cell e to the power of x end cell cell s i n invisible function application 2 x end cell cell t a n invisible function application x squared end cell row cell invisible function application left parenthesis 1 plus x right parenthesis end cell cell c o s invisible function application x end cell cell s i n invisible function application x end cell row cell c o s invisible function application x squared end cell cell e to the power of x minus 1 end cell cell s i n invisible function application x squared end cell end table close vertical bar= A + Bx + Cx2, then B is equal to

    Maths-General
    General
    Maths-

    If ax3 + bx2 + cx + d = open vertical bar table row cell x to the power of 2 end exponent end cell cell left parenthesis x minus 1 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell row cell left parenthesis x minus 1 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 3 right parenthesis to the power of 2 end exponent end cell row cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 3 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 4 right parenthesis to the power of 2 end exponent end cell end table close vertical bar, then

    If ax3 + bx2 + cx + d = open vertical bar table row cell x to the power of 2 end exponent end cell cell left parenthesis x minus 1 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell row cell left parenthesis x minus 1 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 3 right parenthesis to the power of 2 end exponent end cell row cell left parenthesis x minus 2 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 3 right parenthesis to the power of 2 end exponent end cell cell left parenthesis x minus 4 right parenthesis to the power of 2 end exponent end cell end table close vertical bar, then

    Maths-General
    parallel
    General
    Maths-

    integral fraction numerator sin invisible function application x over denominator left parenthesis a plus b c o s invisible function application x right parenthesis squared end fraction d x

    integral fraction numerator sin invisible function application x over denominator left parenthesis a plus b c o s invisible function application x right parenthesis squared end fraction d x

    Maths-General
    General
    Physics-

    The instantaneous values of current and voltage in an ac circuit are i equals 100 sin invisible function application 3 14 t a m p and e equals 200 sin invisible function application left parenthesis 314 t plus pi divided by 3 right parenthesis V respectively. If the resistance is 1 capital omega then the reactance of the circuit will be

    The instantaneous values of current and voltage in an ac circuit are i equals 100 sin invisible function application 3 14 t a m p and e equals 200 sin invisible function application left parenthesis 314 t plus pi divided by 3 right parenthesis V respectively. If the resistance is 1 capital omega then the reactance of the circuit will be

    Physics-General
    General
    Physics-

    An oxide coated filament is useful in vacuum tubes because essentially

    An oxide coated filament is useful in vacuum tubes because essentially

    Physics-General
    parallel
    General
    Physics-

    In an electron gun the control grid is given a negative potential relative to cathode in order to

    In an electron gun the control grid is given a negative potential relative to cathode in order to

    Physics-General
    General
    Physics-

    In Millikan's experiment for the determination of the charge on the electron, the reason for using the oil is

    In Millikan's experiment for the determination of the charge on the electron, the reason for using the oil is

    Physics-General
    General
    Physics-

    If A and B are identical bulbs which bulbs glows brighter

    If A and B are identical bulbs which bulbs glows brighter

    Physics-General
    parallel
    General
    Physics-

    Following figure shows an ac generator connected to a "block box" through a pair of terminals. The box contains possible R, L, C or their combination, whose elements and arrangements are not known to us. Measurements outside the box reveals that
    e = 75 sin (sin omega t) volt, i = 1.5 sin (omega t + 45o) amp then, the wrong statement is

    Following figure shows an ac generator connected to a "block box" through a pair of terminals. The box contains possible R, L, C or their combination, whose elements and arrangements are not known to us. Measurements outside the box reveals that
    e = 75 sin (sin omega t) volt, i = 1.5 sin (omega t + 45o) amp then, the wrong statement is

    Physics-General
    General
    Physics-

    Which of the following plots may represent the reactance of a series LC combination

    Which of the following plots may represent the reactance of a series LC combination

    Physics-General
    General
    Physics-

    The graphs given below depict the dependence of two reactive impedances X1 and X2 on the frequency of the alternating e.m.f. applied individually to them. We can then say that

    The graphs given below depict the dependence of two reactive impedances X1 and X2 on the frequency of the alternating e.m.f. applied individually to them. We can then say that

    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.