CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
8
You visited us 8 times! Enjoying our articles? Unlock Full Access!
Question

If a is unit vector, then |a×^i|2+|a×^j|2+|a×^k|2= ______

A
3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
0
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 2
Let a=a1^i+a2^j+a3^k
Then
|a×^i|2=|a1^i+a2^j+a3^k)×i|2 =|a3^ja2^k|2

Similarly, |a×^j|2=|a1^ka3^i|2
|a×^k|2=|a2^ia1^j|2

Therefore, |a×^i|2+|a×^j|2+|a×^k|2=(a23+a22)+(a21+a23)+(a22+a21)=2|a|2=2

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Test for Collinearity of 3 Points or 2 Vectors
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon