- #1
utkarshakash
Gold Member
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Homework Statement
If abscissa and ordinate of vertex of parabola [itex]y^2+2ax+2by-1=0[/itex] are equal then least possible length of latus rectum is
Homework Equations
The Attempt at a Solution
The give equation can be rewritten as
[itex]\left( y+b \right) ^2 = -2a\left\{ x-\dfrac{1+b^2}{2a} \right\}[/itex]
As given in question
[itex]-b=\dfrac{1+b^2}{2a} \\
1+b^2+2ab=0[/itex]
Length of latus rectum = a/2
But what can be the range of values of a?