Get Answers to all your Questions

header-bg qa

Need solution for RD sharma maths class 12 chapter 23 Scalar or dot product exercise Fill in the blanks question 13

Answers (1)

\pi

Hint:

               Angle between \vec{a} and \vec{b}

Given:

               If \vec{a} , \vec{b} are two non-zero vector \vec{a}.\vec{b}=-\left |\vec{a} \right | . \left |\vec{b} \right |, then angle between \vec{a} and \vec{b} is

Solution:

               \vec{a}.\vec{b}=-\left |\vec{a} \right | . \left |\vec{b} \right |                                                                                                   … (i)

                And we know that \vec{a}.\vec{b}=-\left |\vec{a} \right | . \left |\vec{b} \right |.\cos\theta                                                                     

From (i) we get

-\vec{a}.\vec{b}=-\left |\vec{a} \right | . \left |\vec{b} \right |.\cos\theta\\ \cos \theta =-1\\ \theta =\pi

          

Posted by

Info Expert 29

View full answer

Crack CUET with india's "Best Teachers"

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