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\mathrm{A}^{\prime}(\mathrm{x})=\sin (\mathrm{x}) \text { so } \mathrm{A}^{\prime}(1) \approx 0.84, \mathrm{~A}^{\prime}(2) \approx 0.91, \mathrm{~A}^{\prime}(3) \approx 0.14