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Here is the problem: (2 to the power x minus 1)/x.

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Find the limit of (2 to the power x minus 1) / x as x → 0.

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Indeterminate form 0 over 0 — apply L prime Hôpital prime s rule. Differentiate the numerator and the denominator separately (this is not the quotient rule).

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Simplify.

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Direct substitution. The expression is continuous at x equals 0, so the limit equals its value there.

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So the answer is Limit equals ln(2) approximately 0.6931471806.

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A limit describes the value a function approaches, not necessarily the value it takes. When substitution gives an indeterminate form, the expression is rewritten (L prime Hôpital prime s rule, a conjugate, or logarithms) until substitution works.

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Numerical values from the right agree: f(0.01) equals 0.69555501, f(0.001) equals 0.69338746, f(0.0001) equals 0.6931712, f(0.00001) equals 0.69314958, which checks out.

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Numerical values from the left agree: f(negative 0.01) equals 0.69075046, f(negative 0.001) equals 0.69290701, f(negative 0.0001) equals 0.69312316, f(negative 0.00001) equals 0.69314478, which checks out.