I was wondering someting that is so simple that it baffled me...(adsbygoogle = window.adsbygoogle || []).push({});

When I have the equation

[tex]a x^2+b x+c=0[/tex]

this obviously has the solutions

[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

And when I have the equation

[tex]b x+c=0[/tex]

this has the solution

[tex]x=\frac{-c}{b}[/tex]

My problem now is the limiting case [itex]a\rightarrow 0[/itex] in the upper situation:

[tex]\lim_{a\rightarrow 0}\frac{-b\pm\sqrt{b^2-4ac}}{2a}\rightarrow -\infty\neq\frac{-c}{b}[/tex]

So what's wrong here? Why does this limit not exist?

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# Limit of abc-formula for a->0

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