Consider the ellipse with the equation x2+3y2−2x−6y−2=0.The eccentric angle of a point on the ellipse at a distance 2 units from the contra of the ellipse is
A
π4
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
π2
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
π3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is Aπ4
We have, x2+3y2−2x−6y−2=0.
⇒x2−2x+1−1+3y2−6y+3−3−2=0.
⇒(x−1)2+3(y−1)2=6
⇒(x−1)2+3(y−1)2=6 which becomes x2+3y2=6 on shifting the origin to (1,1). Any point with eccentric angle θ is (√6cosθ,√2sinθ) ⇒4=6cos2θ+2sin2θ⇒4cos2θ=2⇒cosθ=±1√2 ⇒Hence θ=π4