Get Answers to all your Questions

header-bg qa

Please solve RD Sharma class 12 chapter 28 The Plane exercise multiple choice question 21 maths textbook solution

Answers (1)

Answer:

 Option (c)

Hint:

 Use vector dot product for direction.

Given:

 2x - 3y + 6z - 11 = 0

Solution:

We have equation of plane are 2x - 3y + 6z - 11 = 0

Normal to the plane is

\overrightarrow{n} = 2\widehat{i}-3\widehat{j}+6\widehat{k}

Also x-axis is along the vector

\overrightarrow{a} = \widehat{i}+0\widehat{j}+0\widehat{k}

According to the question

\begin{aligned} &sin \alpha =\frac{\left | \overrightarrow{a}.\overrightarrow{n} \right |}{\left | \overrightarrow{a} \right |.\left | \overrightarrow{n} \right |}\\ &=\frac{\left | \widehat{i}.(2\widehat{i}-3\widehat{j}+6\widehat{k}) \right |}{\sqrt{1}.\sqrt{4+9+36}}\\ &=\frac{2}{7} \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