Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • School
  • Please solve RD Sharma class 12 chapter 25 Scalar triple product exercise multiple choice question 17 maths textbook solution

Please solve RD Sharma class 12 chapter 25 Scalar triple product exercise multiple choice question 17 maths textbook solution

Answers (1)

Answer:

 -2

Hint:

 Vectors are coplanar, then their scalar triple product is zero

\begin{aligned} &\therefore \left [ \overrightarrow{a} \quad \overrightarrow{b} \quad \overrightarrow{c} \right ]=\begin{vmatrix} 3 &-1 &2 \\ 2 &1 &3 \\ 1 &\lambda &-1 \end{vmatrix}\\ &=3(-1-3\lambda )+1(-2-3)+2(2\lambda -1)\\ &=-3-9\lambda -2-3+4\lambda -2\\ &=-5\lambda -10 \end{aligned}

As, vectors are coplanar

\begin{aligned} &\left [ \overrightarrow{a} \quad \overrightarrow{b} \quad \overrightarrow{c} \right ]=0\\ &-5\lambda -10=0\\ &\lambda =\frac{10}{-5}\\ &\lambda =-2 \end{aligned}

Posted by

Gurleen Kaur

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads

Similar Questions

Trending Articles/News

anam-khan

CBSE OSM controversy deepens as students allege fresh errors, seek grace marks
anam-khan

CBSE to issue revised Class-12 physical marksheets through regional offices
anam-khan

NEET aspirant Aditya Mishra becomes CBSE Science topper after re-evaluation

Latest Question