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

If the line lx + my = 1 be a tangent to the circle x2+y2=a2, then the locus of the point (l, m) is

A

A straight line

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

A Circle

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

The correct option is B

A Circle


If the line lx + my - 1 = 0 touches the circle x2+y2=a2, then applying the condition of tangency, we have ±l.0+m.01l2+m2=a

On squaring and simplifying, we get the required locus x2+y2=1a2. Hence it is a circle.


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