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Question:

Equation of the ellipse whose axes are the axes of coordinates and which passes through the point (-3, 1) and has eccentricity √2/5 is?

3x²+5y²-32=0

5x²+3y²-32=0

5x²+3y²-48=0

3x²+5y²-15=0

Solution:

Let the ellipse be
x2/a2 + y2/b2 = 1
It passes through (-3, 1) so 9/a2 + 1/b2 = 1 .. (i)
Also, b2 = a2(1-e2) = a2(1-2/5)
∴ 5b2 = 3a2 …(ii)
Solving we get a2 = 32/3, b2 = 32/5
So, the ellipse is 3x2 + 5y2 = 32.
Hence, option '3x²+5y²-32=0' is correct.