Derivative Of Y=e^(√x) A Comprehensive Guide And Step-by-Step Solution

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In the realm of calculus, finding the derivative of a function is a fundamental operation that reveals its rate of change. This article delves into the process of determining the derivative of the function y=exy = e^{\sqrt{x}}, a classic example that showcases the application of the chain rule and the power rule in differentiation. We will embark on a step-by-step journey, carefully dissecting each stage of the derivation to ensure a thorough understanding of the underlying concepts.

Grasping the Essence of Derivatives

Before we immerse ourselves in the intricacies of the problem at hand, it's crucial to establish a firm grasp of the core concept of derivatives. In essence, the derivative of a function, denoted as dydx\frac{dy}{dx}, quantifies the instantaneous rate at which the function's output (yy) changes with respect to its input (xx). Geometrically, the derivative at a specific point represents the slope of the tangent line to the function's graph at that point.

Derivatives are indispensable tools in numerous scientific and engineering disciplines, enabling us to model and analyze dynamic systems, optimization problems, and a plethora of other real-world phenomena. From determining the velocity and acceleration of moving objects to optimizing the design of structures and algorithms, derivatives play a pivotal role.

At its core, finding a derivative involves employing established differentiation rules, such as the power rule, product rule, quotient rule, and the chain rule. The choice of rule hinges on the specific structure of the function being differentiated. For our function, y=exy = e^{\sqrt{x}}, the chain rule will be our primary ally, as it governs the differentiation of composite functions – functions nested within other functions.

Deciphering the Chain Rule

The chain rule, a cornerstone of differential calculus, provides a systematic approach for differentiating composite functions. A composite function is essentially a function within a function, where the output of one function serves as the input for another. Mathematically, if we have y=f(g(x))y = f(g(x)), then the chain rule dictates that:

dydx=dydududx\qquad \frac{dy}{dx} = \frac{dy}{du} \cdot \frac{du}{dx}

where u=g(x)u = g(x).

In simpler terms, the chain rule instructs us to differentiate the outer function with respect to the inner function, then multiply by the derivative of the inner function with respect to xx. This stepwise approach ensures that we account for the interconnected rates of change within the composite function.

Let's illustrate this with an example. Consider the function y=(x2+1)3y = (x^2 + 1)^3. Here, the outer function is f(u)=u3f(u) = u^3 and the inner function is g(x)=x2+1g(x) = x^2 + 1. Applying the chain rule, we first find the derivative of the outer function with respect to uu, which is 3u23u^2. Next, we find the derivative of the inner function with respect to xx, which is 2x2x. Finally, we multiply these two derivatives together, substituting x2+1x^2 + 1 back in for uu:

dydx=3(x2+1)22x=6x(x2+1)2\qquad \frac{dy}{dx} = 3(x^2 + 1)^2 \cdot 2x = 6x(x^2 + 1)^2

The chain rule allows us to systematically tackle the differentiation of complex composite functions by breaking them down into manageable steps.

Embarking on the Differentiation Journey of y=exy = e^{\sqrt{x}}

Now, let's turn our attention back to our main objective: finding the derivative of y=exy = e^{\sqrt{x}}. This function is a classic example of a composite function, where the outer function is the exponential function, eue^u, and the inner function is the square root function, x\sqrt{x}.

To effectively apply the chain rule, we'll introduce a substitution to simplify the expression. Let u=xu = \sqrt{x}. This substitution transforms our function into y=euy = e^u. Now, we can clearly see the outer function (eue^u) and the inner function (u=xu = \sqrt{x}).

The next step is to find the derivatives of both the outer and inner functions. The derivative of the outer function, y=euy = e^u, with respect to uu is simply eue^u, a fundamental property of the exponential function:

dydu=eu\qquad \frac{dy}{du} = e^u

To find the derivative of the inner function, u=xu = \sqrt{x}, with respect to xx, we first rewrite the square root as a power: u=x12u = x^{\frac{1}{2}}. Now, we can apply the power rule, which states that the derivative of xnx^n is nxn1nx^{n-1}. Applying this rule, we get:

dudx=12x12=12x\qquad \frac{du}{dx} = \frac{1}{2}x^{-\frac{1}{2}} = \frac{1}{2\sqrt{x}}

We have now successfully determined the derivatives of both the outer and inner functions. The stage is set to apply the chain rule and unveil the derivative of y=exy = e^{\sqrt{x}}.

Applying the Chain Rule to Unravel the Derivative

With the derivatives of the outer and inner functions in hand, we can now invoke the chain rule to find the derivative of y=exy = e^{\sqrt{x}} with respect to xx. Recall the chain rule formula:

dydx=dydududx\qquad \frac{dy}{dx} = \frac{dy}{du} \cdot \frac{du}{dx}

We have already established that dydu=eu\frac{dy}{du} = e^u and dudx=12x\frac{du}{dx} = \frac{1}{2\sqrt{x}}. Substituting these results into the chain rule formula, we get:

dydx=eu12x\qquad \frac{dy}{dx} = e^u \cdot \frac{1}{2\sqrt{x}}

The final step is to replace uu with its original expression, x\sqrt{x}, to express the derivative solely in terms of xx:

dydx=ex12x\qquad \frac{dy}{dx} = e^{\sqrt{x}} \cdot \frac{1}{2\sqrt{x}}

Thus, the derivative of y=exy = e^{\sqrt{x}} is ex2x\frac{e^{\sqrt{x}}}{2\sqrt{x}}. This expression succinctly captures the instantaneous rate of change of the function with respect to its input.

Summarizing the Differentiation Process

Let's recap the key steps we undertook to find the derivative of y=exy = e^{\sqrt{x}}:

  1. Recognized the function as a composite function, where the outer function was the exponential function and the inner function was the square root function.
  2. Introduced a substitution, u=xu = \sqrt{x}, to simplify the expression and make the application of the chain rule more apparent.
  3. Found the derivatives of both the outer function (eue^u) with respect to uu and the inner function (x\sqrt{x}) with respect to xx.
  4. Applied the chain rule formula, dydx=dydududx\frac{dy}{dx} = \frac{dy}{du} \cdot \frac{du}{dx}, to combine the derivatives of the outer and inner functions.
  5. Substituted back the original expression for uu to express the derivative solely in terms of xx.

By meticulously following these steps, we successfully determined that the derivative of y=exy = e^{\sqrt{x}} is ex2x\frac{e^{\sqrt{x}}}{2\sqrt{x}}.

Significance and Applications of the Derivative

The derivative we have calculated, ex2x\frac{e^{\sqrt{x}}}{2\sqrt{x}}, provides valuable insights into the behavior of the function y=exy = e^{\sqrt{x}}. For instance, it allows us to determine the slope of the tangent line to the function's graph at any point, which in turn reveals the instantaneous rate of change of the function at that point.

Moreover, the derivative can be used to identify intervals where the function is increasing or decreasing. If the derivative is positive over an interval, the function is increasing; conversely, if the derivative is negative, the function is decreasing. Additionally, the derivative can help us locate critical points, which are points where the derivative is either zero or undefined. These critical points often correspond to local maxima or minima of the function.

The function y=exy = e^{\sqrt{x}} and its derivative find applications in various fields, including:

  • Probability and Statistics: The exponential function is a fundamental component of many probability distributions, and its derivative plays a role in analyzing these distributions.
  • Physics: Exponential functions often appear in models of physical phenomena, such as radioactive decay and population growth, and their derivatives are essential for understanding the dynamics of these systems.
  • Engineering: Exponential functions and their derivatives are used in control systems, signal processing, and other engineering applications.

By understanding the derivative of y=exy = e^{\sqrt{x}}, we gain a powerful tool for analyzing and applying this function in a wide range of contexts.

Conclusion: Mastering the Art of Differentiation

In this article, we have embarked on a comprehensive journey to determine the derivative of the function y=exy = e^{\sqrt{x}}. We began by establishing a firm understanding of the concept of derivatives and the chain rule, a crucial tool for differentiating composite functions. We then meticulously applied the chain rule, breaking down the function into its outer and inner components and finding their respective derivatives. Finally, we combined these derivatives to arrive at the expression for the derivative of the original function, ex2x\frac{e^{\sqrt{x}}}{2\sqrt{x}}.

This exploration has not only provided us with the derivative of a specific function but has also reinforced the importance of the chain rule and the systematic approach required for tackling differentiation problems. By mastering these techniques, we equip ourselves with valuable tools for analyzing and understanding the behavior of functions, a skill that is indispensable in various scientific and engineering disciplines.

The world of calculus is vast and fascinating, and the journey of learning derivatives is a crucial step in unlocking its potential. As we continue to explore the intricacies of calculus, we will encounter even more complex functions and differentiation techniques. However, the fundamental principles and problem-solving strategies we have honed in this article will serve as a solid foundation for future endeavors.

Understanding the Derivative of y=e^(√x)

Let's discuss how to find the derivative of the function y=ex{ y = e^{\sqrt{x}} }. This type of problem is common in calculus and involves understanding the chain rule. The chain rule is a fundamental concept when dealing with composite functions, which are functions within functions.

In our case, we have the exponential function eu{ e^u } where u=x{ u = \sqrt{x} }. To find dydx{ \frac{dy}{dx} }, we'll need to differentiate ex{ e^{\sqrt{x}} } with respect to x{ x }. This requires breaking down the problem into manageable parts and applying the chain rule methodically. Our main goal is to provide a clear, step-by-step explanation to ensure you understand each stage of the process thoroughly. We'll focus on how to identify the outer and inner functions, differentiate them separately, and then combine them correctly to get the final derivative. This explanation aims to make the process accessible and understandable for anyone learning calculus, especially when dealing with exponential and square root functions.

To begin, recall that the derivative of eu{ e^u } with respect to u{ u } is simply eu{ e^u }, a fundamental property of exponential functions. Next, we must consider the inner function, x{ \sqrt{x} }, which can also be written as x12{ x^{\frac{1}{2}} }. To differentiate this, we will use the power rule. The power rule states that if you have a function of the form xn{ x^n }, its derivative is nxn1{ nx^{n-1} }. Applying this to x12{ x^{\frac{1}{2}} }, we multiply by the exponent 12{ \frac{1}{2} } and subtract 1 from the exponent, resulting in 12x12{ \frac{1}{2}x^{-\frac{1}{2}} }. This can be simplified to 12x{ \frac{1}{2\sqrt{x}} }. Now we have the pieces we need to apply the chain rule effectively.

Applying the Chain Rule

To successfully differentiate y=ex{ y = e^{\sqrt{x}} }, we must apply the chain rule. The chain rule states that if you have a composite function y=f(g(x)){ y = f(g(x)) }, then the derivative dydx{ \frac{dy}{dx} } is given by dydududx{ \frac{dy}{du} \cdot \frac{du}{dx} }, where u=g(x){ u = g(x) }. This rule essentially breaks down the differentiation of a composite function into manageable parts. In our specific case, f(u)=eu{ f(u) = e^u } and g(x)=x{ g(x) = \sqrt{x} }. Therefore, we need to find the derivative of eu{ e^u } with respect to u{ u }, and the derivative of x{ \sqrt{x} } with respect to x{ x }, and then multiply these results together.

First, we found that the derivative of eu{ e^u } with respect to u{ u } is eu{ e^u }. Second, we determined that the derivative of x{ \sqrt{x} } with respect to x{ x } is 12x{ \frac{1}{2\sqrt{x}} }. Now, we multiply these two derivatives according to the chain rule:

dydx=eu12x{ \frac{dy}{dx} = e^u \cdot \frac{1}{2\sqrt{x}} }

We then substitute u=x{ u = \sqrt{x} } back into the equation:

dydx=ex12x{ \frac{dy}{dx} = e^{\sqrt{x}} \cdot \frac{1}{2\sqrt{x}} }

This gives us the final derivative. Understanding and correctly applying the chain rule is critical in calculus, particularly when dealing with composite functions involving exponential and square root terms. The step-by-step approach of identifying the outer and inner functions, differentiating them separately, and then combining them, ensures an accurate result.

Step-by-Step Calculation

Let’s walk through the step-by-step calculation of the derivative for y=ex{ y = e^{\sqrt{x}} }. This will help solidify your understanding of the chain rule and how it applies to this particular function. We'll break down each step to make it clear and easy to follow. Starting with the original function, our goal is to find dydx{ \frac{dy}{dx} }.

  1. Identify the composite functions: The function y=ex{ y = e^{\sqrt{x}} } is a composite function. We can consider x{ \sqrt{x} } as the inner function and eu{ e^u } as the outer function, where u=x{ u = \sqrt{x} }. Recognizing this structure is crucial for applying the chain rule.

  2. Differentiate the outer function: The outer function is eu{ e^u }. The derivative of eu{ e^u } with respect to u{ u } is simply eu{ e^u }. This is a fundamental derivative rule that needs to be memorized.

  3. Differentiate the inner function: The inner function is x{ \sqrt{x} }, which can be written as x12{ x^{\frac{1}{2}} }. To differentiate this, we use the power rule. The power rule states that the derivative of xn{ x^n } is nxn1{ nx^{n-1} }. Applying this to x12{ x^{\frac{1}{2}} }, we get 12x12{ \frac{1}{2}x^{-\frac{1}{2}} }, which simplifies to 12x{ \frac{1}{2\sqrt{x}} }.

  4. Apply the chain rule: The chain rule states that dydx=dydududx{ \frac{dy}{dx} = \frac{dy}{du} \cdot \frac{du}{dx} }. We have already found dydu=eu{ \frac{dy}{du} = e^u } and dudx=12x{ \frac{du}{dx} = \frac{1}{2\sqrt{x}} }. Now, we multiply these two results together:

    dydx=eu12x{ \frac{dy}{dx} = e^u \cdot \frac{1}{2\sqrt{x}} }

  5. Substitute back for u{ u }: We need to express our derivative in terms of x{ x }, so we substitute u=x{ u = \sqrt{x} } back into the equation:

    dydx=ex12x{ \frac{dy}{dx} = e^{\sqrt{x}} \cdot \frac{1}{2\sqrt{x}} }

  6. Simplify: The final step is to simplify the expression. We can rewrite the derivative as:

    dydx=ex2x{ \frac{dy}{dx} = \frac{e^{\sqrt{x}}}{2\sqrt{x}} }

This step-by-step calculation ensures that we correctly apply the chain rule and power rule to find the derivative of y=ex{ y = e^{\sqrt{x}} }. Breaking down the problem into smaller, manageable steps makes the differentiation process more straightforward and less prone to errors.

Final Result and Its Implications

After carefully applying the chain rule and power rule, we have found that the derivative of y=ex{ y = e^{\sqrt{x}} } is dydx=ex2x{ \frac{dy}{dx} = \frac{e^{\sqrt{x}}}{2\sqrt{x}} }. This result is a key finding in calculus and has several important implications for understanding the behavior of the function y=ex{ y = e^{\sqrt{x}} }.

First, let’s consider what this derivative tells us. The derivative represents the instantaneous rate of change of the function y{ y } with respect to x{ x }. In simpler terms, it gives us the slope of the tangent line to the graph of y=ex{ y = e^{\sqrt{x}} } at any given point x{ x }. This is a crucial concept in many applications, such as optimization problems and curve sketching.

The final result, ex2x{ \frac{e^{\sqrt{x}}}{2\sqrt{x}} }, shows that the derivative is always positive for x>0{ x > 0 }, because both ex{ e^{\sqrt{x}} } and 2x{ 2\sqrt{x} } are positive in this domain. This indicates that the function y=ex{ y = e^{\sqrt{x}} } is always increasing for x>0{ x > 0 }. There are no intervals where the function is decreasing, which simplifies the analysis of its graph.

Additionally, let's consider the implications of the x{ \sqrt{x} } term in the denominator. As x{ x } approaches 0, the denominator approaches 0, and the derivative approaches infinity. This suggests that the tangent line to the graph of y=ex{ y = e^{\sqrt{x}} } becomes steeper and steeper as x{ x } gets closer to 0. However, since the function is only defined for x0{ x \geq 0 }, we don't need to consider negative values of x{ x }.

The exponential term ex{ e^{\sqrt{x}} } in the numerator ensures that the derivative grows rapidly as x{ x } increases. This means that the function y=ex{ y = e^{\sqrt{x}} } increases at an accelerating rate, a characteristic feature of exponential functions. The derivative helps us quantify this rate and understand the function's long-term behavior.

In summary, the derivative dydx=ex2x{ \frac{dy}{dx} = \frac{e^{\sqrt{x}}}{2\sqrt{x}} } provides valuable insights into the increasing nature and rate of change of the function y=ex{ y = e^{\sqrt{x}} }. It is a practical demonstration of how the chain rule and power rule are applied in calculus to reveal significant properties of functions.

Practice Problems

To further solidify your understanding of differentiating composite functions, especially those involving exponential and square root functions, let’s explore some practice problems. Working through these examples will help you apply the chain rule effectively and recognize different variations of these types of problems. The key to mastering calculus is consistent practice and a clear understanding of the fundamental rules.

  1. Problem 1: Find the derivative of y=e2x+1{ y = e^{\sqrt{2x+1}} }

    • This problem extends the original example by adding a linear term inside the square root. The inner function now involves both a square root and a linear expression. You will need to apply the chain rule multiple times to solve this.
  2. Problem 2: Find the derivative of y=ex{ y = \sqrt{e^x} }

    • In this problem, the exponential function is inside the square root. This requires recognizing the composite nature of the function and applying the chain rule accordingly.
  3. Problem 3: Find the derivative of y=ex2+1{ y = e^{\sqrt{x^2+1}} }

    • This example introduces a quadratic term inside the square root, making the inner function a bit more complex. Differentiating this will reinforce your understanding of how to combine the chain rule with other differentiation rules.
  4. Problem 4: Find the derivative of y=exx{ y = \frac{e^{\sqrt{x}}}{x} }

    • This problem combines the derivative of ex{ e^{\sqrt{x}} } with the quotient rule. You will first need to find the derivative of ex{ e^{\sqrt{x}} } using the chain rule, and then apply the quotient rule to the entire expression.
  5. Problem 5: Find the derivative of y=(ex)2{ y = (e^{\sqrt{x}})^2 }

    • This problem involves an exponential function raised to a power. You will need to combine the chain rule with the power rule for differentiation.

By working through these practice problems, you will gain confidence in your ability to differentiate composite functions. Remember to break each problem down into steps, identify the inner and outer functions, differentiate them separately, and then apply the chain rule. Practice is essential for mastering calculus, so take the time to solve these problems carefully.

Conclusion

In this comprehensive exploration, we have thoroughly examined the process of finding the derivative of the function y=ex{ y = e^{\sqrt{x}} }. We started by introducing the basic concepts of derivatives and the chain rule, which are fundamental in calculus. We then systematically applied the chain rule to our function, breaking it down into manageable steps to ensure clarity and accuracy. We identified the outer and inner functions, differentiated them separately, and then combined the results using the chain rule formula. This methodical approach not only allowed us to find the derivative but also provided a deep understanding of the underlying principles.

Our step-by-step calculation highlighted the importance of recognizing composite functions and the strategic application of differentiation rules. We carefully differentiated the outer function (the exponential function) and the inner function (the square root function), ensuring we correctly applied the power rule and the chain rule throughout the process. The final result, dydx=ex2x{ \frac{dy}{dx} = \frac{e^{\sqrt{x}}}{2\sqrt{x}} }, is a testament to the power and precision of calculus techniques.

Furthermore, we discussed the implications of this derivative. We noted that the derivative is always positive for x>0{ x > 0 }, indicating that the function y=ex{ y = e^{\sqrt{x}} } is always increasing in this domain. We also analyzed the behavior of the derivative as x{ x } approaches 0, and how the exponential term in the numerator influences the function’s growth rate. These insights are crucial for understanding the function’s properties and behavior, which is essential in various applications.

Finally, we included a set of practice problems to help you reinforce your understanding and develop your skills in differentiating composite functions. These problems were designed to challenge you in different ways, combining the chain rule with other differentiation rules and variations of the basic function. By working through these examples, you can solidify your knowledge and gain confidence in your ability to tackle more complex calculus problems.

Mastering the derivative of y=ex{ y = e^{\sqrt{x}} } is a significant step in your calculus journey. It demonstrates the application of fundamental principles and the importance of a systematic approach. With a clear understanding of these concepts and consistent practice, you will be well-equipped to handle a wide range of differentiation challenges.