Get Answers to all your Questions

header-bg qa

Explain Solution R.D.Sharma Class 12 Chapter 23 Scalar or Dot Products Exercise 23.1 Question 43 Maths Textbook Solution.

Answers (1)

Answer: Proved

Hint: You must know the rules of solving vectors.

Given: If \vec{a} vector \vec{a} is perpendicular to two non-collinear vector \vec{b} and \vec{c} then show that \vec{a} is \perp to every vector in the plane of   \vec{b} and \vec{c} .

Solution: Given that \vec{a} is perpendicular to  \vec{b} and \vec{c}

\vec{a}\cdot \vec{b}=0  and \vec{a}\cdot \vec{c}=0 

Now, let \vec{x}  be any vector in plane of \vec{b} and \vec{c}

Then, \vec{x} is the linear combination of \vec{b} and \vec{c}

\vec{x}=x \vec{b}+y \vec{c} \text { for some } \mathrm{r} \text { and } \mathrm{y}

Now,

\begin{aligned} &\vec{a} \cdot \vec{x}=\vec{a} \cdot(x \vec{b}+y \vec{c}) \\ &\vec{a} \cdot \vec{x}=x(\vec{a} \cdot \vec{b})+y(\vec{a} \cdot \vec{c}) \\ &\vec{a} \cdot \vec{x}=x(0)+y(0) \\ &\vec{a} \cdot \vec{x}=0 \end{aligned}

Thus, \vec{a} \: is \: perpendicular\: to\: \vec{x}

That \: is, \vec{a} \: is \: perpendicular \: to\: every \: vector \: in \: plane \: \vec{b} \: and \: \vec{c}

Posted by

infoexpert21

View full answer

Crack CUET with india's "Best Teachers"

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