Let →u,→v,→w be such that |→u|=1,|→v|=2,|→w|=3. If the projection of →v along →u is equal to that of →w along →u and →v,→w are perpendicular to each other then |→u−→v+→w| equals
A
√14
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
√7
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
14
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is D√14 Let the angles between →u,→v be α ; →v,→w be β and between →w,→u be γ Here, 2cosα=3cosγ and β=90o ∣∣→u−→v+→w∣∣=√u2+v2+w2+2(→u⋅→w)−2(→u⋅→v)−2(→v⋅→w)=√14+6cosγ−4cosα−0 =√14