Prove that the equation ?x2+ 2xy + y2-2x-1=0 represents
a parabola and find its focus, latus rectum and directrix.
Also trace the curve.
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Answers
Answer:
I DONT KNOW . TRY YOURSELF .
To prove that the equation x2+ 2xy + y2-2x-1=0 represents a parabola, we can try to simplify it by completing the square.
Starting with the given equation:
x²2 + 2xy + y²2 - 2x - 1 = 0
Rearranging terms:
x²2 - 2x + y²2 + 2xy = 1
Completing the square for the x-terms:
(x - 1)²2 - 1 + y²2 + 2xy = 1
(x - 1)²2 + y²2 + 2xy = 2
Completing the square for the y-term:
(x - 1)²2 + (y + x)²2 = 2
Dividing both sides by 2:
[(x - 1)²2 + (y + x)²2]/2 = 1
This is the equation of a parabola centered at (1, -1/2), with the focus at (1, -3/4) and the directrix at y = -1/4.
To find the latus rectum, we can use the formula l = 2F where F is the distance from the vertex to the focus. The vertex is (1, -1/2), and we know the focus is (1, -3/4), so:
F = (1/4)
l = 2F = 1/2
To graph the parabola, we can plot the vertex, focus, and directrix, and use the fact that the parabola is symmetric to sketch its shape.
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