(i+j-k) (i-j+k)= _______ - Vidyadip

MCQ

$(\hat{i}+\hat{j}-\hat{k}) \cdot(\hat{i}-\hat{j}+\hat{k})=$ _______

A
$\hat{ i }-\hat{ j }-\widehat{ k }$
B
$1$
✓
$-1$
D
$-\hat{ j }+\widehat{ k }$

✓

Answer

Correct option: C.

$-1$

$-1$
Explanation:
$(\hat{ i }+\hat{ j }-\widehat{ k }) \cdot(\hat{ i }-\hat{ j }+\widehat{ k })$
$=1+1(-1)+(-1)(1) $
$=1-1-1 $
$=-1$

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 "MCQ" from Question Bank [2022]→Question Bank [2022] — all question types→Maths STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

If $\int_{\log 2}^x \frac{ du }{\left( e ^{ u }-1\right)^{1 / 2}}=\frac{\pi}{6}$, then $e ^x=$

If one of the lines $a x^2$$+2 h x y+b y^2=0$ bisects the angle between the positive coordinate axes, then

If $\log 10\left(\frac{x^3-y^3}{x^3+y^3}\right)=2$, then $\frac{d y}{d x}=$

If the lines represented by $3 y^2+9 x y+k x^2=0$ are perpendicular to each other, then $k=$

If $\bar{a}, \bar{b}, \bar{c}$ are three non-coplanar vectors, then the vector equation $\overline{ r }=(1-p-q) \overline{ a }+p \overline{b}+q \overline{ c }$ represents a

The integral $\int_{\frac{\pi}{4}}^{\frac{3 \pi}{4}} \frac{d x}{1+\cos x}$ is equal to

If the mean and variance of a binomial variate $X$ are $2$ and $1$ respectively, then the probability that $X$ takes a value greater than $1$ is:

$\int\limits^1_0\frac{\text{d}}{\text{dx}}\Big\{\sin^{-1}\Big(\frac{2\text{x}}{1+\text{x}^2}\Big)\Big\}\text{dx}$ is equal to:

If $3\left(\sec ^2 \theta+\tan ^2 \theta\right)=5$, then the general value of $\theta$ is

If $A, B$ are two $n \times n$ non$-$singular matrices, then