Skip to main content \(\require{cancel}\newcommand{\definiteintegral}[4]{\int_{#1}^{#2}\,#3\,d#4}
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\newcommand{\indefiniteintegral}[2]{\int#1\,d#2}
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\newcommand{\vvec}{{\mathbf v}}
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\definecolor{fillinmathshade}{gray}{0.9}
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\newcommand{\sfrac}[2]{{#1}/{#2}}
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Instructions.
Drag the point
\(B\) to move the point on the graph and change the secant line. Notice that there is no well-defined limiting tangent line as
\(x \to 0\text{.}\)
