Another difficult integral/Also question on checking lower limit.

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In summary, the conversation is about a complex integral with various trigonometric functions and limits. The individual is curious about the answer and wonders if the second term approaches negative infinity as theta approaches 0. They also question whether the derivative plays a role and how to find a lower limit.
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Zula110100100
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Homework Statement


[itex]\displaystyle{r^{2}\int^{\arcsin\frac{r}{t}}_{0^{+}}\frac{\sqrt{2}\sin(\theta-\frac{\pi}{4})\sin(2\arcsin(\frac{t}{r}\sin\theta))}{1-\cos(2\theta)}d\theta + \int^{\arcsin\frac{r}{t}}_{0^{+}}\frac{\cos(\frac{\pi}{4}-\theta)}{1-\cos(2\theta)}d\theta - \int^{\arcsin\frac{r}{t}}_{0^{+}}\arcsin(\frac{t}{r}\sin\theta)d\theta + \int^{\arcsin\frac{r}{t}}_{0^{+}}d\theta}[/itex]

[itex] t = \sqrt{2}, r = 1[/itex]

This is once again beyond my skills for quite some time I imagine, but I am extremely curious to know the answer. The number empire integral calculator gives me that the second term approaches -∞ as theta approaches 0. Does this mean then that with 0+ I wind up with -∞ as the answer still? Or since the change in theta gets smaller too does it depend on the derivative? How do I find if there is a lower limit?
 
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Homework Equations \displaystyle{r^{2}\int^{\arcsin\frac{r}{t}}_{0^{+}}\frac{\sqrt{2}\sin(\theta-\frac{\pi}{4})\sin(2\arcsin(\frac{t}{r}\sin\theta))}{1-\cos(2\theta)}d\theta + \int^{\arcsin\frac{r}{t}}_{0^{+}}\frac{\cos(\frac{\pi}{4}-\theta)}{1-\cos(2\theta)}d\theta - \int^{\arcsin\frac{r}{t}}_{0^{+}}\arcsin(\frac{t}{r}\sin\theta)d\theta + \int^{\arcsin\frac{r}{t}}_{0^{+}}d\theta}The Attempt at a Solution I am not sure how to solve this problem.
 

FAQ: Another difficult integral/Also question on checking lower limit.

What is an integral?

An integral is a mathematical concept that represents the area under a curve in a graph. It is used to find the total value or quantity of something, such as finding the total distance traveled by an object given its velocity over a certain time period.

What makes an integral difficult?

An integral can be difficult if it does not have a simple closed-form solution, meaning it cannot be solved using basic algebraic operations. Additionally, the function being integrated may be complex or the limits of integration may be difficult to determine.

How do you solve a difficult integral?

Solving a difficult integral often involves using advanced integration techniques such as substitution, integration by parts, or trigonometric identities. It may also require breaking the integral into smaller, more manageable parts.

What is the purpose of checking the lower limit in an integral?

Checking the lower limit in an integral is important because it ensures that the function being integrated is well-defined at that point. This helps to avoid mathematical errors or undefined solutions.

What are some common mistakes to avoid when solving integrals?

Common mistakes when solving integrals include forgetting to include the constant of integration, using the wrong substitution or integration technique, and making errors in algebraic calculations. It is important to double-check all steps and simplify as much as possible before arriving at a final solution.

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