Use Coupon: CART20 and get 20% off on all online Study Material

Total Price: Rs.

There are no items in this cart.
Continue Shopping
Grade: 12th pass
If a, b are non collinear vectors 
and r+r Cross a=b then r=
one year ago

Answers : (1)

Aditya Gupta
2014 Points
the first thing to be said about this ques is that it is really hard and uses several principles. to solve the ques, take 
r= xa+yb+z(axb) …. the reason why we can do this is coz a, b and a cross b are LINEARLY INDEPENDENT. 
now plug in this value of r in the given eqn, and then you will have to use gthe formula for vector triple product which says:
ax(bxc)= (a.c)b – (a.b)c
after doing all of this, you will get an eqn of the form
ea+fb+g(axb)=0 where e f and g are expressions in x y and z.
but due to linear independence, e=f=g=0
so solving these 3 eqns in e variables x y and z you will get
and x= (a.b)/(1+|a|^2)
hence, r= xa+yb+z(axb) has been correctly determined!
one year ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies

Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution

Course Features

  • 19 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions

Ask Experts

Have any Question? Ask Experts

Post Question

Answer ‘n’ Earn
Attractive Gift
To Win!!! Click Here for details