WEBVTT
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here we have a composite function and we're going to
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identify the inside function and the outside function, and
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we'll call the inside function G of X. So
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we see inside the parentheses we have co tangent of
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X, and then the outside function will call that
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f of X. So we see outside the parentheses
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we have signed. So the f of X,
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the outside function will be the sign of X.
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Now we're going to find the derivative D. Y
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. D X, and will use the chain rule
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which tells us to start by taking the derivative of
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the outside function. So we take the derivative of
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sign, which is co sign So we have co
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sign of co tangent X. We still have the
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inside in there. Now we multiply that by the
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derivative of the inside function and the derivative of co
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tangent X is negative coast. He can't squared X
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. So here we have our derivative and what we
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can do if we want to simplify it is just
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right. The negative Cosi can't squared X part first
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, so it's going to look like negative Cosi can't
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squared. X Times CO sign of co tangent X