JEE MAIN - Mathematics (2007)

  • 1
    The average marks of boys in a class is 52 and that of girls is 42. The average marks of boys and girls combined is 50. The percentage of boys in the class is
    پاسخ دهید
    (A)
    80
  • 2
    The function $$f:R/\left\{ 0 \right\} \to R$$ given by

    $$f\left( x \right) = {1 \over x} - {2 \over {{e^{2x}} - 1}}$$

    can be made continuous at $$x$$ = 0 by defining $$f$$(0) as
    پاسخ دهید
    (B)
    1
  • 3
    Let $$f:R \to R$$ be a function defined by

    $$f(x) = \min \left\{ {x + 1,\left| x \right| + 1} \right\}$$, then which of the following is true?
    پاسخ دهید
    (A)
    $$f(x)$$ is differentiale everywhere
  • 4
    The largest interval lying in $$\left( { - {\pi \over 2},{\pi \over 2}} \right)$$ for which the function

    $$f\left( x \right) = {4^{ - {x^2}}} + {\cos ^{ - 1}}\left( {{x \over 2} - 1} \right)$$$$ + \log \left( {\cos x} \right)$$,

    is defined, is
    پاسخ دهید
    (B)
    $$\left[ {0,{\pi \over 2}} \right)$$
  • 5
    If sin-1$$\left( {{x \over 5}} \right)$$ + cosec-1$$\left( {{5 \over 4}} \right)$$ = $${\pi \over 2}$$, then the value of x is :
    پاسخ دهید
    (D)
    3
  • 6
    If a line makes an angle of $$\pi /4$$ with the positive directions of each of $$x$$-axis and $$y$$-axis, then the angle that the line makes with the positive direction of the $$z$$-axis is :
    پاسخ دهید
    (B)
    $${\pi \over 2}$$
  • 7
    Two aeroplanes $${\rm I}$$ and $${\rm I}$$$${\rm I}$$ bomb a target in succession. The probabilities of $${\rm I}$$ and $${\rm I}$$$${\rm I}$$ scoring a hit correctly are $$0.3$$ and $$0.2,$$ respectively. The second plane will bomb only if the first misses the target. The probability that the target is hit by the second plane is :
    پاسخ دهید
    (D)
    0.32
  • 8
    The area enclosed between the curves $${y^2} = x$$ and $$y = \left| x \right|$$ is :
    پاسخ دهید
    (A)
    $$1/6$$
  • 9
    Let $$I = \int\limits_0^1 {{{\sin x} \over {\sqrt x }}dx} $$ and $$J = \int\limits_0^1 {{{\cos x} \over {\sqrt x }}dx} .$$ Then which one of the following is true?
    پاسخ دهید
    (B)
    $$1 < {2 \over 3}$$ and $$J < 2$$
  • 10
    The solution for $$x$$ of the equation $$\int\limits_{\sqrt 2 }^x {{{dt} \over {t\sqrt {{t^2} - 1} }} = {\pi \over 2}} $$ is
    پاسخ دهید
    (D)
    None
  • 11
    Let $$F\left( x \right) = f\left( x \right) + f\left( {{1 \over x}} \right),$$ where $$f\left( x \right) = \int\limits_l^x {{{\log t} \over {1 + t}}dt,} $$ Then $$F(e)$$ equals
    پاسخ دهید
    (C)
    $$1/2$$
  • 12
    $$\int {{{dx} \over {\cos x + \sqrt 3 \sin x}}} $$ equals
    پاسخ دهید
    (C)
    $$\,{1 \over 2}\,\log \,\tan \,\left( {{x \over 2} + {\pi \over {12}}} \right) + C$$
  • 13
    If $$D = \left| {\matrix{ 1 & 1 & 1 \cr 1 & {1 + x} & 1 \cr 1 & 1 & {1 + y} \cr } } \right|$$ for $$x \ne 0,y \ne 0,$$ then $$D$$ is :
    پاسخ دهید
    (D)
    divisible by both $$x$$ and $$y$$
  • 14
    If $$p$$ and $$q$$ are positive real numbers such that $${p^2} + {q^2} = 1$$, then the maximum value of $$(p+q)$$ is
    پاسخ دهید
    (C)
    $${\sqrt 2 }$$
  • 15
    The function $$f\left( x \right) = {\tan ^{ - 1}}\left( {\sin x + \cos x} \right)$$ is an incresing function in
    پاسخ دهید
    (D)
    $$\left( { - {\pi \over 2},{\pi \over 4}} \right)$$
  • 16
    If $$\widehat u$$ and $$\widehat v$$ are unit vectors and $$\theta $$ is the acute angle between them, then $$2\widehat u \times 3\widehat v$$ is a unit vector for :
    پاسخ دهید
    (B)
    exactly one value of $$\theta $$
  • 17
    For the Hyperbola $${{{x^2}} \over {{{\cos }^2}\alpha }} - {{{y^2}} \over {{{\sin }^2}\alpha }} = 1$$ , which of the following remains constant when $$\alpha $$ varies$$=$$?
    پاسخ دهید
    (B)
    abscissae of foci
  • 18
    Let A $$\left( {h,k} \right)$$, B$$\left( {1,1} \right)$$ and C $$(2, 1)$$ be the vertices of a right angled triangle with AC as its hypotenuse. If the area of the triangle is $$1$$ square unit, then the set of values which $$'k'$$ can take is given by :
    پاسخ دهید
    (A)
    $$\left\{ { - 1,3} \right\}$$
  • 19
    In a geometric progression consisting of positive terms, each term equals the sum of the next two terns. Then the common ratio of its progression is equals
    پاسخ دهید
    (B)
    $$\,{1 \over 2}\left( {\sqrt 5 - 1} \right)$$
  • 20
    In the binomial expansion of $${\left( {a - b} \right)^n},\,\,\,n \ge 5,$$ the sum of $${5^{th}}$$ and $${6^{th}}$$ terms is zero, then $$a/b$$ equals
    پاسخ دهید
    (B)
    $${{n - 4} \over 5}$$
  • 21
    The set S = {1, 2, 3, ........., 12} is to be partitioned into three sets A, B, C of equal size. Thus $$A \cup B \cup C = S,\,A \cap B = B \cap C = A \cap C = \phi $$. The number of ways to partition S is
    پاسخ دهید
    (A)
    $${{12!} \over {{{(4!)}^3}}}\,\,$$
  • 22
    If the difference between the roots of the equation $${x^2} + ax + 1 = 0$$ is less than $$\sqrt 5 ,$$ then the set of possible values of $$a$$ is
    پاسخ دهید
    (C)
    $$\left( { - 3,3} \right)$$
  • 23
    If $$\,\left| {z + 4} \right|\,\, \le \,\,3\,$$, then the maximum value of $$\left| {z + 1} \right|$$ is :
    پاسخ دهید
    (A)
    6
  • 24
    Let $$L$$ be the line of intersection of the planes $$2x+3y+z=1$$ and $$x+3y+2z=2.$$ If $$L$$ makes an angle $$\alpha $$ with the positive $$x$$-axis, then cos $$\alpha $$ equals
    پاسخ دهید
    (C)
    $${1 \over {\sqrt 3 }}$$