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 Class 10, 12 private exams 2026-27 registration begins on cbse.gov.in, check eligibility and fees
anam-khan

CBSE Date Sheet 2027 LIVE: Form filling for Class 10, 12 private students closes on Oct 23; exam dates soon
anam-khan

CBSE Board Exams 2027 LIVE: Class 12, 10 time table soon at cbse.gov.in; passing marks, OSM marking

Latest Question