MCQ
$\sqrt { - 2} \,\sqrt { - 3} = $
  • A
    $\sqrt 6 $
  • $ - \sqrt 6 $
  • C
    $i\sqrt 6 $
  • D
    None of these

Answer

Correct option: B.
$ - \sqrt 6 $
b
(b) $\sqrt { - 2} \sqrt { - 3} = i\sqrt 2 \,i\,\sqrt 3 = {i^2}\sqrt 6 = - \sqrt 6 $
.

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

Similar questions

A unit vector perpendicular to the plane containing the vectors $i - j + k$ and $ - i + j + k$ is
If $\alpha $ and $\beta $ are solutions of $sin^2\,x + a\, sin\, x + b = 0$ as well that of $cos^2\,x + c\, cos\, x + d = 0$ , then $sin\,(\alpha + \beta )$ is equal to
A committee of five is to be chosen from a group of $9$ people. The probability that a certain married couple will either serve together or not at all, is
If ${{({e^x} + 2)} \over {({e^x} - 1)\,(2{e^x} - 3)}} = - {3 \over {{e^x} - 1}} + {B \over {2{e^x} - 3}}$, then $B = $
Let ${ }^{n} C_{r-1}=28,{ }^{n} C_{r}=56$ and ${ }^{n} C_{r+1}=70$. Let $\mathrm{A}(4 \cos t, 4 \sin t), \mathrm{B}(2 \sin t,-2 \cos t)$ and $\mathrm{C}\left(3 \mathrm{r}-\mathrm{n}, \mathrm{r}^{2}-\mathrm{n}-1\right)$ be the vertices of a triangle $A B C$, where $t$ is a parameter. If $(3 x-1)^{2}+(3 y)^{2}=\alpha$, is the locus of the centroid of triangle ABC , then $\alpha$ equals :
The value of $\tan {20^o} + 2\tan {50^o} - \tan {70^o}$ is equal to
Three positive numbers form an increasing $G.P.$ If the middle term in this $G.P.$ is doubled, the new numbers are in $A.P.$ then the common ratio of the $G.P.$ is:
Let $f(x)$ be continuous and differentiable function for all reals.

$f(x + y)\, = \,f(x) - 3xy + f(y).$ If  $\mathop {\lim }\limits_{h \to 0} \frac{{f(h)}}{h} = 7$ then value of $f'(x)$ is-

If $A(1,\,2,\,3),\,B( - 1, - 1, - 1)$ be the points, then the distance $AB$ is
If $x + \frac{1}{x} = 2\cos \alpha $, then ${x^n} + \frac{1}{{{x^n}}} = $