wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

If a, b and c are unit vectors, then the maximum value of |ab|2+|bc|2+|ca|2 is

A
1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
4
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
9
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution

The correct option is C 9
|ab|2+|bc|2+|ca|2=2(a2+b2+c2)2(a.b+b.c+c.a)=2×32(a.b+b.c+c.a)=6(a+b+c)2+a2+b2+c2=9|a+b+c|2

The minimum value of |a+b+c| is 0. Hence, the maximum value of |ab|2+|bc|2+|ca|2 is 9 - 0 which is 9.

flag
Suggest Corrections
thumbs-up
12
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Unit Vectors
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon