Download App

1. relation and function — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMaths1. relation and function1 Mark
MCQ
If $f:R \to R$, then $f(x) = \;|x|$ is
  • A
    One-one but not onto
  • B
    Onto but not one-one
  • C
    One-one and onto
  • ✓
    None of these
✓

Answer

Correct option: D.
None of these
d
(d) $f( - 1) = f(1) = 1$;

$\therefore $function is many-one function.

Obviously, $f$ is not onto so $ f$ is neither one-one nor onto.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 1. relation and function→1. relation and function — all question types→Maths STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Consider the cube in the first octant with sides $OP, OQ $and $OR$ of length $1$ , along the $x$-axis, $y$-axis and $z$-axis, respectively, where $O (0,0,0)$ is the origin. Let $S \left(\frac{1}{2}, \frac{1}{2}, \frac{1}{2}\right)$ be the centre of the cube and $T$ be the vertex of the cube opposite to the origin $O$ such

that $S$ lies on the diagonal OT. If $\overrightarrow{ p }=\overrightarrow{ SP }, \overrightarrow{ q }=\overrightarrow{ SQ }, \overrightarrow{ r }=\overrightarrow{ SR }$ and $\overrightarrow{ t }=\overrightarrow{ ST }$, then the value of $|(\overrightarrow{ p } \times \overrightarrow{ q }) \times(\overrightarrow{ r } \times \overrightarrow{ t })|$ is. . . . . . .. 

→
If A is a matrix of order m×n and B is a matrix such that ABT and BTA are both defined, then the order of matrix B is:
  1. m×n
  2. n×n
  3. n×m
  4. m×n
→
A bag ‘$A$’ contains $2$ white and $3$ red balls and bag ‘$B$’ contains $4$ white and $5$ red balls. One ball is drawn at random from a randomly chosen bag and is found to be red. The probability that it was drawn from bag $‘B’$ was
→
Consider the function $f (x) = x^3 - 8x^2 + 20x -13$
The function $f (x)$ defined for $R \rightarrow R$
→
The foot of perpendicular of the point $(2,0,5)$ on the line $\frac{x+1}{2}=\frac{y-1}{5}=\frac{z+1}{-1}$ is $(\alpha, \beta, \gamma)$. Then. Which of the following is $NOT$ correct?
→
If $f(a) = a^2 + a+ 1$ , then number of solutions of equation $f(a^2) = 3f(a)$ is
→
The order and the degree of the differential equation $\left(1+3 \frac{d y}{d x}\right)^2=4 \frac{d^3 y}{d x^3}$ respectively are
→
If $A$ and $B$ are two square matrices of order $3$ such that $AB = A$ and $BA = B$ and matrices $X$,$Y$ and $Z$ are defined as $(X = A^4 + B^4)$, $Y$ = $A^{10}+ B^{10},$ then the matrix $X -Y$ is
→
While measuring the side of an equilateral triangle an error of k % is made, the percentage error in its area is:
  1. k%
  2. 2k%
  3. $\frac{\text{K}}{2}\%$
  4. 3k%
→
List $I$ List $II$
$P.$ Let $y(x)=\cos \left(3 \cos ^{-1} x\right), x \in[-1,1], x \neq \pm \frac{\sqrt{3}}{2}$. Then $\frac{1}{y(x)}\left\{\left(x^2-1\right) \frac{d^2 y(x)}{d x^2}+x \frac{d y(x)}{d x}\right\}$ equals $1.$ $1$
$Q.$ Let $A_1, A_2, \ldots \ldots, A_n(n>2)$ be the vertices of a regular polygon of $n$ sides with its centre at the origin. Let $\vec{a}_k$ be the position vector of the point $A_k, k=1,2, \ldots, n$. If $\left|\sum_{k=1}^{n-1}\left(\overrightarrow{a_k} \times \overrightarrow{a_{k+1}}\right)\right|=\left|\sum_{k=1}^{n-1}\left(\overrightarrow{a_k} \cdot \overrightarrow{a_{k+1}}\right)\right|$, then the minimum value of $n$ is $2.$ $2$
$R.$ If the normal from the point $P(h, 1)$ on the ellipse $\frac{x^2}{6}+\frac{y^2}{3}=1$ is perpendicular to the line $x+y=8$, then the value of $h$ is $3.$ $8$
$S.$ Number of positive solutions satisfying the equation $\tan ^{-1}\left(\frac{1}{2 x+1}\right)+\tan ^{-1}\left(\frac{1}{4 x+1}\right)=\tan ^{-1}\left(\frac{2}{x^2}\right)$ is $4.$ $9$

Codes: $ \quad P \quad Q \quad R \quad S $

→