Some functions and their graphs -i - class-XI

A comprehensive quiz on mathematical functions for Class XI, covering identity functions, constant functions, polynomial functions, linear functions, and rational functions, including properties like injectivity, continuity, periodicity, function composition, inverses, and functional equations.

46 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

If $p = q$ then $px =$ ________

  1. $q$
  2. $qx$
  3. $q + x$
  4. $0$
Question 2 Multiple Choice (Multiple Answers)

Which of the following functions are identity functions?

  1. $f:R\rightarrow R, f(x) = x$
  2. $g : N \rightarrow Z, g(p)= 3$
  3. $h:z \rightarrow z, h(y)=y$
  4. $g:N\rightarrow N, g(z) =z$
Question 3 Multiple Choice (Single Answer)

If ${ (x, 2), (4, y) }$ represents an identity function, then $( x, y)$ is :

  1. (2, 4)
  2. (4, 2)
  3. (2, 2)
  4. (4, 4)
Question 4 Multiple Choice (Single Answer)

Which of the following functions is/are constant ?

  1. $f(x)=x^{2}+2$
  2. $f(x)=x+\dfrac{1}{x}$
  3. $f(x)=7$
  4. $f(x)=6+x$
Question 5 Multiple Choice (Single Answer)

An identity function is a?

  1. Many to many function
  2. One to One function
  3. Many to one function
  4. None
Question 6 Multiple Choice (Single Answer)

State whether the following statement is True or False.
The inverse of an identity function is the identity function itself.

  1. True
  2. False
Question 7 Multiple Choice (Single Answer)

Let $f:\mathbb{R}\rightarrow \mathbb{R}$ be a function such that for any irrational number $r,$ and any real number $x$ we have $f(x)=f(x+r)$. Then, $f$ is

  1. an identity function
  2. a constant function
  3. a zero function
  4. onto function
Question 8 Multiple Choice (Single Answer)

The graph of an Identity function is?

  1. A straight line parallel to X axis
  2. A straight line parallel to Y axis
  3. A straight line passing through the origin
  4. None
Question 9 Multiple Choice (Single Answer)

Let $f$ be a linear function for which $f (6)  - f (2) = 12$. The value of $f (12) - f(2)$ is equal the 

  1. $12$
  2. $18$
  3. $24$
  4. $30$
Question 10 Multiple Choice (Single Answer)

The set values of $x$ for which function $f(x)=x\ln {x}-x+1$

  1. $\left( 1,\infty \right) $
  2. $\left( \cfrac { 1 }{ e } ,\infty \right) $
  3. $[e,\infty )$
  4. $\left( 0,1 \right) \cup \left( 1,\infty \right) $
Question 11 Multiple Choice (Single Answer)

Let $f$ be an injective map with domain {x, y, z} and range {1, 2, 3} such that exactly one of the following statements is correct and the remaining are false :
$f (x) = 1, f (y) \sqrt 1, f (z) \sqrt 2$. The value of $f^{-1} (1)$ is

  1. x
  2. y
  3. z
  4. none of these
Question 12 Multiple Choice (Single Answer)

$c \to c,,is,defined,as,f\left( x \right) = \frac{{ax + b}}{{cx + d}},,bd \ne 0$.then f is a constant function when

  1. a=c
  2. b=d
  3. ad=bc
  4. ab=cd
Question 13 Multiple Choice (Single Answer)

$f:c \to c$ is defined as $f(x) = \dfrac{{ax + b}}{{cx + d}},bd \ne 0$ then $f$ is a constant function when,

  1. a=c
  2. b=d
  3. ad=bc
  4. ab=cd
Question 14 Multiple Choice (Single Answer)

If $f(n+1)=f(n)$ for all $n\in N, f(7)=5$  then  $f(35)=$

  1. $25$
  2. $49$
  3. $35$
  4. $5$
Question 15 Multiple Choice (Single Answer)

Let $f(x)$ is a cubic polynomial with real coefficients, $x\ \in R$ such that $f"(3)=0,\ f'(5)=0$  
If $f(3)=1$ and $f(5)=-3$, then $f(1)$ is equal to

  1. $2$
  2. $3$
  3. $5$
  4. $6$
Question 16 Multiple Choice (Single Answer)

The complete set of values of $x$ for which the function $f(x)=2\tan^{-1}x+\sin^{-1} \dfrac{2x}{1+x^{2}}$ behaves like a constant function with positive output is equal to

  1. $x \in [-1,1]$
  2. $[1,\infty)$
  3. $(-\infty,1]$
  4. $(-\infty, -1] \cup [1,\infty)$
Question 17 Multiple Choice (Single Answer)

Let f be a polynomial function such that $f(3x)=f'(x).f"(x)$, for all $x\epsilon R$. Then :

  1. $f(2)+f'(2)=28$
  2. $f"(2)-f'(2)=0$
  3. $f"(2)-f(2)=4$
  4. $f(2)-f'(2)+f"(2)=10$
Question 18 Multiple Choice (Single Answer)

If  $f \left( \dfrac { x + y } { 2 } \right) = \dfrac { f ( x ) + f ( y ) } { 2 }$  for all  $x , y \in R$  and  $f ^ { \prime } ( o ) = - 1 , f ( o ) = 1$  then  $f(2)=$

  1. $\dfrac { 1 } { 2 }$
  2. $1$
  3. $-1$
  4. $\dfrac { -1 } { 2 }$
Question 19 Multiple Choice (Single Answer)

let $f(x)$ be a polynomial of degree $4$ having extreme values at $x=2$.if $\underset { x\rightarrow 0 }{ lim } \left( \frac { f\left( x \right)  }{ { x }^{ 2 } } +1 \right) =3$ then $f(1)$

  1. $\frac { 1 }{ 2 } $
  2. $\frac { 3 }{ 2 } $
  3. $\frac { 5 }{ 2 }$
  4. $\frac { 9 }{ 2 } $
Question 20 Multiple Choice (Single Answer)

If $\alpha$ and $\beta$ are the polynomial  $f(x)=x^2-5x+k$ such that $\alpha-\beta=1$, then value of k is 

  1. $8$
  2. $6$
  3. $\dfrac{13}{2}$
  4. $4$
Question 21 Multiple Choice (Single Answer)

If $y^2 = ax^2 +bx+c$, then $y^2 \dfrac{d^2y}{dx^2}$ is

  1. a constant function
  2. a function of x only
  3. a function of y only
  4. a function of both x and y
Question 22 Multiple Choice (Single Answer)

If $fxln\left(1+\dfrac{1}{x}\right)dx=p(x)ln\left(1+\dfrac{1}{x}\right)+\dfrac{1}{2}x-\dfrac{1}{2}ln(1+x)+c$, being arbitary costant, then

  1. $p(X)=\dfrac{1}{2}x^{2}$
  2. $p(x)=0$
  3. $p(x)=1$
  4. $none\ of\ these$
Question 23 Multiple Choice (Single Answer)

Let $f(x)$ is cubic polynomial with real coefficient such that $f''(3) = 0, f'(5) = 0$. If $f(3) = 1$ and $f(5) = -3$, then $f(1)$ is equal to

  1. $2$
  2. $3$
  3. $5$
  4. $6$
Question 24 Multiple Choice (Single Answer)

$f (x) = x^4 - 10x^3 + 35x^2 - 50x + c$ is a constant. the number of real roots of . f (x) = 0 and 
f'' (x) = 0 are respectively 

  1. 1 , 0
  2. 3, 2
  3. 1 , 2
  4. 3 , 0
Question 25 Multiple Choice (Single Answer)

Let $\displaystyle f(x)=ax^{2}+bx+c,$ where $a,b,c$ are rational, and $f: Z\rightarrow Z,$ where $Z$ is the set of integers. Then $a+b$ is

  1. a negative integer
  2. an integer
  3. nonintegral rational number
  4. none of these
Question 26 Multiple Choice (Single Answer)

The positive integers $x$ for which $f(x)=x^{3}-8x^{2}+20x-13$ is a prime is

  1. $2$
  2. $3$
  3. $4$
  4. $5$
Question 27 Multiple Choice (Single Answer)

If $f\quad \left( x \right) ={ x }^{ 2 }+2bx+{ 2c }^{ 2 }\quad and\quad g\quad (x)\quad ={ -x }^{ 2 }\quad -2cx+{ b }^{ 2 }\quad are\quad such\quad that\quad min\quad f\quad (x)\quad >\quad max\quad g\quad (x),\quad then$ relation between b and c, is

  1. none relation
  2. 0 < c < b/2
  3. $\left| c \right| <\frac { \left| b \right| }{ \sqrt { 2 } } $
  4. $\left| c \right| >\sqrt { 2 } \left| b \right| $
Question 28 Multiple Choice (Single Answer)

If $f(x)$ is a polynomial function satisfying $f(x)f\left(\dfrac{1}{x}\right)=f(x)+\left(\dfrac{1}{x}\right)$ and $f(3)=28$, then $f(4)=$

  1. $63$
  2. $65$
  3. $66$
  4. $27$
Question 29 Multiple Choice (Single Answer)

If $f\left(x\right)$ is a polynomial such that $ f\left(a\right) f\left(b\right)<0$, then number of zeros lieing between $a$ and $b$ is 

  1. $one$
  2. $at least one$
  3. $two$
  4. $at most 2$
Question 30 Multiple Choice (Single Answer)

If $ P ( X ) = x ^ { 3 } - 3 x ^ { 2 } + 2 x + 5 $ and P ( a ) = P ( b ) = P ( c ) = 0 then the value of ( 2 - a ) ( 2 - b ) ( 2 - c ) is

  1. 3
  2. 5
  3. 7
  4. 9
Question 31 Multiple Choice (Single Answer)

If f : R $\rightarrow$ R, g : R $\rightarrow$ R and h : R $\rightarrow$ R is such that $f(x) = x^2, g(x) = tan  x$ and $h(x) = log  x$, then the value of [ho(gof)], if $x = \displaystyle \dfrac{\pi}{2}$ will be

  1. 0
  2. 1
  3. -1
  4. 10
Question 32 Multiple Choice (Single Answer)

If f is a constant function and f(100)=100  then f(2007)=_____

  1. 2007
  2. 100
  3. 0
  4. None of these
Question 33 Multiple Choice (Single Answer)

The number of elements of an identity function defined on a set containing four elements is______

  1. $\displaystyle 2^{2}$
  2. $\displaystyle 2^{4}$
  3. $\displaystyle 2^{8}$
  4. $\displaystyle 2^{16}$
Question 34 Multiple Choice (Single Answer)

On differentiating an identity function, we get?

  1. Signum function
  2. Sinc function
  3. Constant function
  4. None
Question 35 Multiple Choice (Single Answer)

If $f,g,h$ are three functions from a set of positive real numbers into itself satisfying the condition,
$f(x) \cdot g(x)=h \sqrt{x^2 + y^2}$ such that $x,y \epsilon (0,\infty)$.then, $\dfrac{f(x)}{g(x)}$ is a?

  1. Constant function
  2. Identity function
  3. Zero function
  4. Signum function
Question 36 Multiple Choice (Single Answer)

A constant function is a periodic function.

  1. True
  2. False
Question 37 Multiple Choice (Single Answer)

Let $f(-2, 2)\rightarrow(-2, 2)$ be a continuous function given $f(x)=f{(x}^{2})$. Given $f(0)=\dfrac{1}{2}$ then the $4f(\dfrac{1}{2})$

  1. $4$
  2. $2$
  3. $-2$
  4. $1$
Question 38 Multiple Choice (Single Answer)

If $f\left( x \right)$ is a function satisfying  $f\left( x \right).f\left( {\frac{1}{x}} \right) = f\left( x \right) + f\left( {\frac{1}{x}} \right)$ and $f\left( 4 \right) = 65$ then find $f\left( 6 \right)$

  1. $217$
  2. $215$
  3. $-216$
  4. $-217$
Question 39 Multiple Choice (Single Answer)

Let $f\left( x \right) = p{x^2} + qx - \left( {{a^2} + {b^2} + {c^2} - ab - bc - ca} \right),,\left( {p,q,a,b,c \in R} \right)(a,b,c$ are distinct). If both roots of $f(x)=0$ are non-real, then 

  1. $2\left( {p + q} \right) - \left[ {{{\left( {a - b} \right)}^2} + {{\left( {b - c} \right)}^2} + {{\left( {c - a} \right)}^2}} \right] > 0$
  2. $2\left( {p + q} \right) - \left[ {{{\left( {a - b} \right)}^2} + {{\left( {b - c} \right)}^2} + {{\left( {c - a} \right)}^2}} \right] < 0$
  3. $p - 2q - 2 - \left[ {{{\left( {a - b} \right)}^2} + {{\left( {b - c} \right)}^2} + {{\left( {c - a} \right)}^2}} \right] < 0$
  4. $p - 2q - 2 - \left[ {{{\left( {a - b} \right)}^2} + {{\left( {b - c} \right)}^2} + {{\left( {c - a} \right)}^2}} \right] > 0$
Question 40 Multiple Choice (Multiple Answers)

If $f(x)$ is a polynomial function satisfying the condition $f(x) \times f\left(\dfrac{1}{x}\right)=f(x)+f\left(\dfrac{1}{x}\right)$ and $f(2)=9$ then

  1. $2f(4) =3 f(6)$
  2. $14f(1) = f(3)$
  3. $ 9f(3) = 2f(5)$
  4. $f(10) = f(11)$
Question 41 Multiple Choice (Multiple Answers)

If $\displaystyle f(x)=27x^{3}+\frac{1}{x^{3}}$ and $\alpha,\beta$ are the roots of $\displaystyle 3x+\frac{1}{x}=2$ is

  1. $f(\alpha)=f(\beta)$
  2. $f(\alpha)=10$
  3. $f(\beta)=-10$
  4. none of these
Question 42 Multiple Choice (Multiple Answers)

If a function satisfies $(x-y)f(x+y)-(x+y)f(x-y)=2(x^{2}y-y^{3}),\forall x,y\in R$ and $ f(1)=2,$ then

  1. $f(x)$ must be polynomial function
  2. $f(3)=12$
  3. $f(0)=0$
  4. $f(x)$ may not be differentiable
Question 43 Multiple Choice (Single Answer)

If $g(x)$ is a polynomial satisfying $g(x) g(y) = g(x) + g(y) + g(xy) - 2$ for all real $x$ and $y$ and $g(2) = 5$ then $g(3)$ is equal  to -

  1. $10$
  2. $24$
  3. $21$
  4. none of these
Question 44 Multiple Choice (Single Answer)

Write a rational function $f$ that has vertical asymptote at $x=4$, a horizontal asymptote at $y=5$ and a zero at $x=-7$.

  1. $f(x)=\dfrac{5(x-7)}{(x-4)}$
  2. $f(x)=\dfrac{5(x+7)}{(x-4)}$
  3. $f(x)=\dfrac{5(x-7)}{(x+4)}$
  4. $f(x)=\dfrac{(x+7)}{(x+4)}$
Question 45 Multiple Choice (Single Answer)

A large mixing tank currently contains $200$ gallons of water into which $10$ pounds of sugar have been mixed. A tap will open pouring $20$ gallons per minute of water into the tank at the same time sugar is poured into the tank at a rate of $2$ pound per minute. Find the concentration (pounds per gallon) of sugar in the tank after $14$ minutes. Then 

  1. the concentration is greater than at the beginning?
  2. the concentration lesser than at the beginning?
  3. the concentration equal to the concentration at the beginning?
  4. None of the above