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| Logarithmic Differentiation |
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| When we want to differentiate a function of the form f(x) g(x), we use logarithmic differentiation. |
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| Let y = f(x) g(x) |
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| Taking log on both sides, we have logy = g(x) logf(x). |
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| Differentiating with respect to x, we get, |
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| Example: |
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| Differentiate the function y = (sin x)cos x. |
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| Suggested answer: |
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| y = (sin x)cos x |
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| Taking log on both sides, we have log y = cos x (log sin x) |
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| Differentiating both sides with respect to x, we have |
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