Solve Complicated Integral: 4+ 8/πx +O(x²) at x→0

  • Thread starter wel
  • Start date
  • Tags
    Integral
In summary, the conversation discusses the integral of a function and how it can be simplified using integration by parts. It is noted that this method can be complicated due to a large exponential term, but by considering the case when x is very small, a suitable expansion of the exponential function can be made, resulting in a simpler integral. The conversation then suggests an alternative method of using a power series expansion to simplify the integral.
  • #1
wel
Gold Member
36
0
Consider the integral
\begin{equation}
I(x)=\int^{2}_{0} (1+t) e^{xcos[\pi (t-1)/2]} dt
\end{equation}
show that
\begin{equation}
I(x)= 4+ \frac{8}{\pi}x +O(x^{2})
\end{equation}
as $$x\rightarrow0.$$

=> Using integration by parts, but its too complicated for me because of huge exponential term.
please help me.
 
Physics news on Phys.org
  • #2
Notice that you are only to consider the case when x is very small, tending to zero. This means you can make a suitable expansion of the exponential function, leaving a much simpler integral.
 
  • #3
CAF123 said:
Notice that you are only to consider the case when x is very small, tending to zero. This means you can make a suitable expansion of the exponential function, leaving a much simpler integral.

Or maybe do this:
$$I=I(0)+I'(0)x+O(x^2)$$
:rolleyes:
 

FAQ: Solve Complicated Integral: 4+ 8/πx +O(x²) at x→0

1. What is an integral?

An integral is a mathematical concept used to find the area under a curve. It is a fundamental tool in calculus and is used to solve a wide range of problems in physics, engineering, and other fields.

2. What does the notation "x→0" mean?

"x→0" indicates that the value of x is approaching 0. In this context, it means that we are looking at the behavior of the integral as x gets closer and closer to 0.

3. How do you solve a complicated integral?

Solving a complicated integral involves applying various techniques and rules from calculus, such as substitution, integration by parts, and partial fractions. It also requires a good understanding of algebra and manipulation of equations.

4. What does "O(x²)" mean in the given integral?

"O(x²)" is the notation for the Big O notation, which is used in mathematics to describe the limiting behavior of a function. In this context, it means that as x approaches 0, the integral will behave similarly to a quadratic function with a coefficient of x².

5. Can this integral be solved analytically?

Yes, this integral can be solved analytically by applying the above-mentioned techniques and rules. However, the process may be complex and time-consuming, so it is often more efficient to use numerical methods or software to approximate the solution.

Back
Top