e1=1−184=97=37
e1=1+94=913=313
Also,
15e12+3e22=k⇒k=15(97)+3(913)
∴k=16
JEE Main 2020 — Mathematics Coordinate Geometry
If e1 and e2 are the eccentricities of the ellipse 18x2+4y2=1 and the hyperbola 9x2−4y2=1 respectively and (e1,e2) is a point on the ellipse 15x2+3y2=k , then the value of k is equal to
Held on 9 Jan 2020 · Verified 6 Jul 2026.
16
17
15
14
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