Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  JEEMAIN and AIPMT  >>  Mathematics  >>  Class12  >>  Vector Algebra
0 votes

If $\overrightarrow b\:\:is\:\: \perp\:\:to \:\:\overrightarrow a+\overrightarrow b\:\:and\:\:\overrightarrow a\:\:is\:\:\perp \:\:to\:\:2\overrightarrow b+\overrightarrow a$ then $|\overrightarrow a|=?$

Can you answer this question?

1 Answer

0 votes
Given: $\overrightarrow b$ is $\perp$ to $\overrightarrow a+\overrightarrow b$ and $\overrightarrow a$ is $\perp$ to $2\overrightarrow b+\overrightarrow a$
$\Rightarrow\:\overrightarrow b.(\overrightarrow a+\overrightarrow b)=0\:\:and\:\:\overrightarrow a.(2\overrightarrow b+\overrightarrow a)=0$
$\Rightarrow\:\overrightarrow a.\overrightarrow b+|\overrightarrow b|^2=0\:\:and\:\:2\overrightarrow a.\overrightarrow b+|\overrightarrow a|^2=0$
$\Rightarrow\:|\overrightarrow a|^2=2|\overrightarrow b|^2$
or $|\overrightarrow a|=\sqrt 2 |\overrightarrow b|$
answered Dec 8, 2013 by rvidyagovindarajan_1

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App