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\({\left( {{a^x}} \right)^\prime } = {a^x}\ln a\,\,\,\left( {a > 0,\,a \ne 1} \right)\).

\({\left( {{a^x}} \right)^\prime } = \frac{{{a^x}}}{{\ln a}}\,\,\,\left( {a > 0,\,a \ne 1} \right)\).

\({\left( {{a^x}} \right)^\prime } = {a^x}\,\,\,\left( {a > 0,\,a \ne 1} \right)\).

\({\left( {{a^x}} \right)^\prime } = x\ln a\,\,\,\left( {a > 0,\,a \ne 1} \right)\).