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

The angle between the lines whose direction cosines satisfy the equations
l+m+n=0 and l2=m2+n2, is


A

π3

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B

π4

No worries! We‘ve got your back. Try BYJU‘S free classes today!
C

π6

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

π2

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A

π3


We know that, angle between two lines is
cos θ=a1a2+b1b2+c1c2a21+b21+c21a22+b22+c22l+m+n=0l=(m+n)(m+n)2=l2m2+n2+2mn=m2+n2 [2=m2+n2,given]2mn=0When m=0 l=nHence, (l,m,n) is (1,0,1).When n=0, then l=mHence,(l,m,n) is (1,0,1). cos θ=1+0+02×2=12θ=π3


flag
Suggest Corrections
thumbs-up
47
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Direction Cosines and Direction Ratios
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon