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Differentiate the function, and fin f(x)=4x+(3)/(x),x=-5

User Olshansky
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Final Answer:

The derivative of the function
\( f(x) = 4x + (3)/(x) \) is
\( f'(x) = 4 - (3)/(x^2) \), and when evaluated at
\( x = -5 \) ,
\( f'(-5) = 4 - (3)/((-5)^2) = (13)/(25) \).

Step-by-step explanation:

To differentiate the function
\( f(x) = 4x + (3)/(x) \), we apply the rules of differentiation. The derivative of
\(4x\) is \(4\), and the derivative of
\((3)/(x)\) is
\(-(3)/(x^2)\) . Combining these results, we obtain
\(f'(x) = 4 - (3)/(x^2)\).

To find
\(f'(-5)\), we substitute
\(x = -5\) into the derivative expression, resulting in
\(f'(-5) = 4 - (3)/((-5)^2) = 4 - (3)/(25) = (97)/(25)\). Therefore, the derivative of
\(f(x)\) at \(x = -5\) is \((13)/(25)\).

Understanding the process of differentiation is fundamental in calculus. It allows us to find the rate at which a function is changing at a specific point. In this case, the derivative
\(f'(x)\) represents the slope of the tangent line to the graph of
\(f(x)\) , and evaluating it at
\(x = -5\) provides the instantaneous rate of change at that point.

User Melicent
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