/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 103 Explain why it is obvious, witho... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Explain why it is obvious, without any calculation, that \(\frac{d}{d x} e^{\ln x}=1\).

Short Answer

Expert verified
The derivative is 1 because \(e^{\ln x} = x\) and the derivative of \(x\) is 1.

Step by step solution

01

Understanding the Expression

The expression given is \(e^{\ln x}\). We need to understand what this expression represents before we differentiate it.
02

Simplifying the Expression

Since the exponential and logarithmic functions are inverses, the expression \(e^{\ln x}\) simplifies directly to \(x\). This is because the exponential function 'undoes' the natural logarithm, returning the original value \(x\).
03

Differentiating the Simplified Expression

Now that we know \(e^{\ln x} = x\), we need to differentiate \(x\) with respect to \(x\). The derivative of \(x\) is simply 1.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Exponentials
Exponentials play a fundamental role in mathematics, especially in calculus. An exponential expression involves a base, which in many cases is the constant \(e\), raised to a power or exponent. The number \(e\) is approximately equal to 2.71828, and it forms the basis of natural exponential functions. Exponential functions grow rapidly and have unique properties that make them very important in calculus and real-world applications.
Understanding how exponential functions interact with other mathematical functions helps in simplifying expressions. For instance, functions like \(e^{\ln x}\) show how exponentials can undo their inverse operations, in this case, logarithms. This is why when you apply the exponential function \(e\) to \(\ln x\), it simplifies to \(x\). This simplification is a key step in differentiating exponential expressions because it often reduces them to more manageable forms.
In general, the derivative of an exponential function, especially those involving \(e\), takes on special forms. For example, \(\frac{d}{dx}e^x = e^x\), which highlights the rate of growth exponential functions can exhibit. This property makes exponential differentiation straightforward and predictable.
Logarithmic Functions
Logarithmic functions are the inverse of exponential functions, and they help us solve problems related to exponential growth and decay. The natural logarithm, denoted as \(\ln x\), is a logarithm with the base \(e\). When you take the natural logarithm of a number, you are essentially asking how many times you must multiply \(e\) by itself to get that number.
In calculus, understanding the properties of logarithmic functions simplifies solving complex differentiation problems. A key property is that \(e^{\ln x} = x\). This is essential because it offers a shortcut in simplifying expressions before differentiating. The logarithmic function effectively "undoes" the exponential function, bringing us back to the original value \(x\).
Further, differentiation of the natural logarithm is straightforward: \(\frac{d}{dx}\ln x = \frac{1}{x}\). This simple rule makes it easier to handle equations where logarithms and powers are involved. Interconnecting exponentials and logarithms through such identities allows for simplification in differentiation tasks.
Differentiation
Differentiation is a fundamental concept in calculus that deals with finding the rate at which a function is changing at any given point. It is the process of finding the derivative of a function. The derivative represents the slope of the tangent line to the curve of the function at a point.
In calculus, differentiating a simple linear function such as \(f(x) = x\) is straightforward. The derivative of \(x\) is \(1\), reflecting the constant rate of change. In more complex problems, such as exponential or logarithmic functions, differentiation is crucial for understanding dynamic changes within the functions.
This is applicable in demonstrating why \(\frac{d}{dx}e^{\ln x} = 1\) is obvious—by simplifying \(e^{\ln x}\) to \(x\), as exponentials and logarithms cancel each other out. Differentiation then becomes direct, as we are left with \(x\), whose derivative is always \(1\). Differentiation enables studying and interpreting function behavior, offering insights into the changes and tendencies expressed mathematically.

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Most popular questions from this chapter

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