Question:medium

The equations of the tangents to the ellipse \(\frac{x^2}{16}+\frac{y^2}{9} = 1\) making an inclination of \(30^{\circ}\) with the major axis are

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Use \(y=mx\pm\sqrt{a^2m^2+b^2}\) with \(m=\tan30^{\circ}\).
Updated On: Oct 1, 2026
  • \(x+\sqrt{3}\,y\pm \sqrt{43} = 0\)
  • \(x-\sqrt{3}\,y\pm \sqrt{43} = 0\)
  • \(\sqrt{3}\,x-y\pm \sqrt{43} = 0\)
  • \(x-\sqrt{3}\,y\pm \sqrt{3} = 0\)
Show Solution

The Correct Option is B

Solution and Explanation

Step 1: Use the condition for tangency
A line $y=mx+c$ touches the ellipse when $c^2=a^2m^2+b^2$.

Step 2: Apply
With $m=1/\sqrt3$, $c^2=\frac{16}{3}+9=\frac{43}{3}$, $c=\pm\sqrt{43/3}$. Rearranging $y=x/\sqrt3+c$ gives $x-\sqrt3y\pm\sqrt{43}=0$, option (B).

Final Answer:
Option (B) gives the tangents. \[ \boxed{x-\sqrt3\,y\pm\sqrt{43}=0} \]
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