To solve the integral of the function \(\frac{(a^x + b^x)^2}{a^x b^x}\), we can start by simplifying the expression. The goal is to rewrite the integrand in a way that makes it easier to integrate. Let's break it down step by step.
Simplifying the Integrand
First, we can rewrite the integral as follows:
\[\int \frac{(a^x + b^x)^2}{a^x b^x} \, dx = \int \left( \frac{(a^x + b^x)^2}{a^x} \cdot \frac{1}{b^x} \right) \, dx\]
Expanding the Square
Next, we expand \((a^x + b^x)^2\):
\[(a^x + b^x)^2 = a^{2x} + 2a^x b^x + b^{2x}\]
Substituting this back into our integral gives:
\[\int \frac{a^{2x} + 2a^x b^x + b^{2x}}{a^x b^x} \, dx\]
Breaking Down the Integral
Now, we can split the integral into three separate parts:
\[\int \left( \frac{a^{2x}}{a^x b^x} + 2 \frac{a^x b^x}{a^x b^x} + \frac{b^{2x}}{a^x b^x} \right) \, dx = \int \left( \frac{a^{2x}}{b^x} + 2 + \frac{b^{2x}}{a^x} \right) \, dx\]
Further Simplification
Now, we can rewrite the integral as:
\[\int \left( a^{x} b^{-x} + 2 + b^{x} a^{-x} \right) \, dx\]
Integrating Each Term
At this stage, we can integrate each term individually:
- For the term \(a^{x} b^{-x}\):
We can rewrite it as \(\left(\frac{a}{b}\right)^{x}\). The integral becomes:
\[\int \left(\frac{a}{b}\right)^{x} \, dx = \frac{b}{\ln\left(\frac{a}{b}\right)} \left(\frac{a}{b}\right)^{x} + C_1\]
- For the constant term 2:
The integral is straightforward:
\[\int 2 \, dx = 2x + C_2\]
- For the term \(b^{x} a^{-x}\):
This can be rewritten as \(\left(\frac{b}{a}\right)^{x}\), and the integral becomes:
\[\int \left(\frac{b}{a}\right)^{x} \, dx = \frac{a}{\ln\left(\frac{b}{a}\right)} \left(\frac{b}{a}\right)^{x} + C_3\]
Combining Results
Now, let's combine all the results from our integrations:
\[\int \frac{(a^x + b^x)^2}{a^x b^x} \, dx = \frac{b}{\ln\left(\frac{a}{b}\right)} \left(\frac{a}{b}\right)^{x} + 2x + \frac{a}{\ln\left(\frac{b}{a}\right)} \left(\frac{b}{a}\right)^{x} + C\]
Here, \(C\) is the constant of integration that combines \(C_1\), \(C_2\), and \(C_3\). This gives us the final expression for the integral. If you have any further questions or need clarification on any of the steps, feel free to ask!