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Following the steps below, use logarithmic differentiation to determine the derivative of the function f(x)= (1+2x)^1/x / sin(x)

a. Take the natural log of both sides and use properties of logarithms to expand the function: ln(f(x))=ln((1+2x)^(x1)csc(x)) b. Take the derivative implicitly: f(x)/f (x) = c. Solve for f ' (x) and replace f(x) with the original function definition: f' (x)=

User Evgeny
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2 Answers

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a. Taking the natural log on both sides,
In(f(x))=(In (1+2x) )/(x) - In \ sin (x) }

b. Taking the derivative implicitly, we have:
(f'(x))/(f(x))=-(In(1+2x))/(x^2)+(2)/(x(1+2x))-cot (x)

c.
f'(x) =((1+2x)^(1/x))/(sin (x)) \Big [ -(In (1+2x))/(x^2)+(2)/(x(1+2x))-cot (x) \Big]

Calculating the derivative of a function

The derivative of the given function can be calculated by following the step-by-step process.

Given that:


f(x)=((1+2x)^(1/x))/(sin(x))

We use the logarithm properties to expand the function, and take the natural log (㏑) on both sides; we have:


In(f(x))=In \Big( ((1+2x)^(1/x))/(sin (x) ) \Big)


In(f(x))=In ((1+2x)^(1/x) - In \ sin (x) }


In(f(x))=(1)/(x) In ((1+2x) - In \ sin (x) }


In(f(x))=(In (1+2x) )/(x) - In \ sin (x) }

b.
In(f(x))=(In (1+2x) )/(x) - In \ sin (x) }

Taking the implicit derivative corresponding to x;


(d)/(dx)In(f(x))= (d)/(dx)\Big ((In (1+2x) )/(x) - In \ sin (x) } \Big )


(1)/(f(x))(d)/(dx)f(x) =(d)/(dx)(In(1+2x)x^(-1))-(d)/(dx) In sin(x))

By implementing the product rule;


(1)/(f(x))f'(x) = In (1+2x) (d)/(dx)x^(-1)+x^(-1) (d)/(dx)In (1+2x) -(1)/(sin (x))(d)/(dx)(sin(x))


(1)/(f(x))f'(x) = In (1+2x) (-x^(-2)) + (x^(-1))/(1+2x)(d)/(dx)(1+2x)-(1)/(sin (x))(cos (x))


(1)/(f(x))f'(x)=-(In(1+2x))/(x^2)+(1)/(x(1+2x))(2)-cot(x)


(f'(x))/(f(x))=-(In(1+2x))/(x^2)+(2)/(x(1+2x))-cot (x)

c. Solving for f'(x) and replacing f(x) with the original function, we have:


f'(x) = f(x) \Big [ -(In(1+2x))/(x^2)+(2)/(x(1+2x))-cot (x) \Big]

provided that:
f(x) = ((1+2x)^(1/x))/(sin (x)), then:


f'(x) =((1+2x)^(1/x))/(sin (x)) \Big [ -(In (1+2x))/(x^2)+(2)/(x(1+2x))-cot (x) \Big]

User Bahar
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4 votes

Final answer:

The derivative of the function
\(f(x) = ((1+2x)^(1/x))/(\sin(x))\) is given by \(f'(x) = ((1+2x)^(1/x))/(\sin(x)) \cdot \left((1)/(x) - \ln(1+2x) -\cot(x)\right)\). This expression reflects the rate of change of the original function, incorporating the intricate interplay of exponential, logarithmic, and trigonometric components.

Step-by-step explanation:

To find the derivative of the given function
\(f(x) = ((1+2x)^(1/x))/(\sin(x))\), we'll use logarithmic differentiation.

1. Take the natural log:

Start by taking the natural logarithm of both sides:


\[\ln(f(x)) = \ln\left((1+2x)^(1/x) \cdot \csc(x)\right)\]

2. Expand using properties of logarithms:

Apply logarithmic properties to expand the expression:


\[\ln(f(x)) = (1)/(x) \cdot \ln(1+2x) - \ln(\sin(x))\]

3. Take the derivative implicitly:

Differentiate both sides implicitly with respect to
\(x\):


\[(f'(x))/(f(x)) = (1)/(x) - (1)/(\sin(x)) - \cot(x)\]

4. Solve for
\(f'(x)\):

Solve for
\(f'(x)\) by multiplying both sides by
\(f(x)\) and replacing
\(f(x)\)with the original function:


\[f'(x) = ((1+2x)^(1/x))/(\sin(x)) \cdot \left((1)/(x) - \ln(1+2x) - \cot(x)\right)\]

The natural logarithm allows us to simplify the expression by using logarithmic properties. Taking the derivative implicitly involves differentiating each term on both sides. The result is an expression for
(f'(x)\) in terms of the original function
(f'(x)\). The key steps include recognizing the chain rule and logarithmic differentiation principles. The final expression captures the rate of change of the given function with respect to
\(x\), incorporating the intricacies of the original function's structure.

User Cameron Martin
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