18 lines
353 B
Markdown
18 lines
353 B
Markdown
$$
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\begin{gathered}
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f(x)=\begin{cases}
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\cfrac{2x^{2}-x-1}{x-1} &x\ne1\\
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-1 &x = 1
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\end{cases}\\\\\\
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D_{f}=\mathbb{R}\\
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\lim_{x\rightarrow1}\frac{2x^{2}-x-1}{x-1}=^{[\frac{0}{0}]}\lim_{x\rightarrow1}\frac{2(x-1)(x+\frac{1}{2})}{x-1}=\lim_{x\rightarrow1}2x+1=3\\
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f(1)=-1\\
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\Delta=1+8\\
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\sqrt{\Delta}=3\\
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x_{1}=1\\
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x_{2}= -\frac{1}{2}
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\end{gathered}
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$$ |