CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
0
You visited us 0 times! Enjoying our articles? Unlock Full Access!
Question

If a, b, c are three non-coplanar vectors and p, q, r are reciprocal vectors, then (la+mb+nc).(lp+mq+nr) is equal to

A
l+m+n
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
l3+m3+n3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
l2+m2+n2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
None of these
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C l2+m2+n2
p, q and r are reciprocal vectors of a, b and c respectively.
So, p.a=1, p.b=0=p.c
q.a=0,q.b=1,q.c=0
r.a=0, r.b=0, r.c=1
(la+mb+nc).(lp+mq+nr)
=l2ap+m2bq+n2cr
=l2+m2+n2
Hence, option C is correct.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Questions
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon