Download App

10. vector algebra — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMaths10. vector algebra1 Mark
MCQ
If $a = (1,\,\, - 1)$ and $b = ( - \,2,\,m)$ are two collinear vectors, then $m =$ 
  • A
    $4$
  • B
    $3$
  • ✓
    $2$
  • D
    $0$
✓

Answer

Correct option: C.
$2$
c
(c) Condition for collinearity, $b = \lambda a$

$ \Rightarrow ( - 2i + mj) = \lambda (i - j)$

Comparison of coefficient, we get

$ \Rightarrow \lambda = - 2$ and $ - \lambda = m.$ So, $m = 2$.

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 10. vector algebra→10. vector algebra — all question types→Maths STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Let $\begin{vmatrix}\text{x}&2&\text{x}\\\text{x}^2&\text{x}&6\\\text{x}&\text{x}&6\end{vmatrix}=\text{ax}^4+\text{bx}^3+\text{cx}^2+\text{dx}+\text{e}.$ Then, the value of 5a + 4b + 3c + 2d + e is equal to:
  1. 0
  2. -16
  3. 16
  4. None of these.
→
If $ \frac{3\text{x}+1}{(\text{x}-1)(\text{x}+3)} = \frac{\text{A}}{\text{x}-1}+\frac{B}{\text{x}+3} $ then $ {\sin}^{-1} \frac{\text{A}}{\text{B}} :$

  1. $ \frac{\pi}{2}$

  2. $ \frac{\pi}{3}$

  3. $ \frac{\pi}{6}$

  4. $ \frac{\pi}{8}$

→
If $f(x)=\int \frac{5 x^{8}+7 x^{6}}{\left(x^{2}+1+2 x^{7}\right)^{2}} d x,(x \geq 0), f(0)=0$ and $f(1)=\frac{1}{K},$ then the value of $K$ is
→
The derivative of $\tan x -x$ with respect to $x$ is
→
If $f(a) = a^2 + a+ 1$ , then number of solutions of equation $f(a^2) = 3f(a)$ is
→
The value of $\sin\bigg[\cos^{-1}\Big(\frac{7}{25}\Big)\bigg]$ is:
  1. $\frac{25}{24}$
  2. $\frac{25}{7}$
  3. $\frac{24}{25}$
  4. $\frac{7}{24}$
→
The derivative of the function, $f(x)=cos^{-1} \left\{ \,\frac{1}{{\sqrt {13} }}(2\cos x - 3\sin x)\,\,\,\right\}$

$ + sin^{-1} \left\{ \,\frac{1}{{\sqrt {13} }}(2\cos x + 3\sin x)\,\,\,\right\} $ w.r.t. at $x = \frac{3}{4}$ is :

→
Find the general solution of: $\frac{\text{dy}}{\text{dx}}=\text{y}\sin\text{x:}$
  1. y + log sin x + c = 0
  2. log y - cos x - c = 0
  3. log y + cos x - c = 0
  4. None of the above
→
If the system of linear equations $2 x-3 y=\gamma+5$ ; $\alpha x+5 y=\beta+1$, where $\alpha, \beta, \gamma \in R$ has infinitely many solutions, then the value of $|9 \alpha+3 \beta+5 \gamma|$ is equal to
→
If $\text{f}(\text{x})=\text{e}^{\text{x}}\sin\text{x}$ in $[0,\pi],$ then c in Rolle's theorem is:
  1. $\frac{\pi}{6}$
  2. $\frac{\pi}{4}$
  3. $\frac{\pi}{2}$
  4. $\frac{3\pi}{4}$
→