If a and b are mutually perpendicular vectors, then (a + b)^2 = - Vidyadip

MCQ

If $a$ and $ b$ are mutually perpendicular vectors, then ${(a + b)^2} = $

A
$a + b$
B
$a - b$
C
$a^2 -b^2$
✓
${(a - b)^2}$

✓

Answer

Correct option: D.

${(a - b)^2}$

d
(d) It is obvious, since $a\,.\,b = 0.$

Hence ${(a + b)^2} = {a^2} + {b^2} = {(a - b)^2}.$

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 STD 12 - 10. vector algebra→STD 12 - 10. vector algebra — all question types→Mathematics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

The probability that a relation $R$ from $\{ x , y \}$ to $\{ x , y \}$ is both symmetric and transitive, is equal to

For any positive integer $n$, define $f_n:(0, \infty) \rightarrow R$ as

$f_n(x)=\sum_{j=1}^n \tan ^{-1}\left(\frac{1}{1+(x+j)(x+j-1)}\right) \text { for all } x \in(0, \infty)$

(Here, the inverse trigonometric function $\tan ^{-1} x$ assumes values in $\left(-\frac{\pi}{2}, \frac{\pi}{2}\right)$ )

Then, which of the following statement(s) is (are) TRUE?

$(A)$ $\sum_{ j =1}^5 \tan ^2\left( f _{ j }(0)\right)=55$

$(B)$ $\sum_{ j =1}^{10}\left(1+ f _{ j }^{\prime}(0)\right) \sec ^2\left( f _{ j }(0)\right)=10$

$(C)$ For any fixed positive integer $n$, $\lim _{x \rightarrow \infty} \tan \left(f_n(x)\right)=\frac{1}{n}$

$(D)$ For any fixed positive integer $n, \lim _{x \rightarrow \infty} \sec ^2\left(f_n(x)\right)=1$

The differential equation whose solution is $(x -h)^2 + (y -k)^2 = a^2$ is ($a$ is a constant)

If $\vec{a}, \vec{b}$ and $(\vec{a}+\vec{b})$ are all unit vectors and $\theta$ is the angle between $\vec{a}$ and $\vec{b}$, then the value of $\theta$ is:

The area of region $\{ \,(x,\,y):{x^2} + {y^2} \le 1 \le x + y\} $ is

Let $f: R \rightarrow R$ be a differentiable function that satisfies the relation $f ( x + y )= f ( x )+ f ( y )-1, \forall x$, $y \in R$. If $f ^{\prime}(0)=2$, then $|f(-2)|$ is equal to $.........$.

$\int(\frac{\cos2\theta-1}{\cos2\theta+1})\text{d}\theta=$

For a binomial variate X, if $\text{n}=3$ and $\text{P(X}=1)=8\text{ P(X = 3}),$ then p =

Let $f$ be a twice differentiable function on $R$. If $f^{\prime}(0)=4$ and $f(x)+\int_{0}^{x}(x-t) f^{\prime}(t) d t=\left(e^{2 x}+e^{-2 x}\right) \cos 2 x+\frac{2}{a} x$ then $(2 a+1)^{5} a^{2}$ is equal to $\dots\dots$

If $A$ and $B$ are matrices of the same order, then $AB^T - BA^T$ is :