Email
Chat with tutor
logo

Ask Questions, Get Answers

X
 
Questions  >>  JEEMAIN and NEET  >>  Mathematics  >>  Class12  >>  Matrices
Answer
Comment
Share
Q)

If $A=\begin{bmatrix}0&2\\3&-4\end{bmatrix}$ and $kA=\begin{bmatrix}0&3a\\2b&24\end{bmatrix}$ then the values of $k,a,b$ are respectively

$\begin{array}{1 1}(A)\;-6,-12,-18&(B)\;-6,4,9\\(C)\;-6,-4,-9&(D)\;-6,12,18\end{array}$

1 Answer

Comment
A)
Given $kA=\begin{bmatrix}0&3a\\2b&24\end{bmatrix}$
$\Rightarrow k\begin{bmatrix}0&2\\3&-4\end{bmatrix}=\begin{bmatrix}0&3a\\2b&24\end{bmatrix}$
$\Rightarrow 2k=3a$
$\Rightarrow 3k=2b$
$\Rightarrow -4k=24$
$2k=3a$
$a=\large\frac{2k}{3}$
$3k=2b$
$b=\large\frac{3k}{2}$
$-4k=24$
$k=-6$
$a=\large\frac{2(-6)}{3}$$=-4$
$b=\large\frac{3(-6)}{2}$$=-9$
Hence (C) is the correct answer.
Help Clay6 to be free
Clay6 needs your help to survive. We have roughly 7 lakh students visiting us monthly. We want to keep our services free and improve with prompt help and advanced solutions by adding more teachers and infrastructure.

A small donation from you will help us reach that goal faster. Talk to your parents, teachers and school and spread the word about clay6. You can pay online or send a cheque.

Thanks for your support.
Continue
Please choose your payment mode to continue
Home Ask Homework Questions
Your payment for is successful.
Continue
Clay6 tutors use Telegram* chat app to help students with their questions and doubts.
Do you have the Telegram chat app installed?
Already installed Install now
*Telegram is a chat app like WhatsApp / Facebook Messenger / Skype.
...