Integral of a continuously differentiable function on [a,b].

In summary, the integral of a continuously differentiable function on [a,b] is the signed area under the curve of the function between the limits of a and b. This is different from a Riemann integral, which is a limit of a sum of rectangles, and a Lebesgue integral, which is a limit of a sum of rectangles over a partition of the domain. The integral can be calculated using various techniques such as the Fundamental Theorem of Calculus, and it has many practical applications in fields such as physics and engineering. The relationship between the integral and its antiderivative is known as the Fundamental Theorem of Calculus.
  • #1
rsa58
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0
suppose f is real, continuously differentiable function on [a,b], f(a)=f(b)=0 and

integral f^2dx=1

show [integral(xf(x)f'(x)dx)= -1/2 over [a,b]
 
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  • #2
How can you write the term [tex]f(x)\,f'(x)[/tex]?
 
  • #3
rsa58 said:
suppose f is real, continuously differentiable function on [a,b], f(a)=f(b)=0 and

integral f^2dx=1

show [integral(xf(x)f'(x)dx)= -1/2 over [a,b]
Integrate by parts:

You will get 1/2(bf2(b)-af2(a)-integral(a,b)f2(x))
 
  • #4
Elaborating on Rainbow Child's suggestion, what is the derivative of (f(x))2?
 

Related to Integral of a continuously differentiable function on [a,b].

What is the definition of an integral of a continuously differentiable function on [a,b]?

The integral of a continuously differentiable function on [a,b] is the signed area under the curve of the function between the limits of a and b.

What is the difference between a Riemann integral and a Lebesgue integral?

A Riemann integral is defined as the limit of a sum of areas of rectangles under a curve, while a Lebesgue integral is defined as the limit of a sum of areas of rectangles over a partition of the domain. The Lebesgue integral is able to integrate a wider range of functions, including non-continuous and unbounded functions.

How is the integral of a continuously differentiable function on [a,b] calculated?

The integral of a continuously differentiable function on [a,b] is typically calculated using one of several integration techniques, such as the Fundamental Theorem of Calculus, integration by parts, or substitution. The method used depends on the specific function being integrated.

What is the relationship between the integral of a continuously differentiable function and its antiderivative?

The integral of a continuously differentiable function on [a,b] is equal to the difference between its antiderivative evaluated at the upper limit b and its antiderivative evaluated at the lower limit a. This relationship is known as the Fundamental Theorem of Calculus.

What are some applications of integrals of continuously differentiable functions on [a,b]?

The integral of a continuously differentiable function on [a,b] has many practical applications, such as calculating the area under a curve, finding the average value of a function, and calculating displacement, velocity, and acceleration in physics and engineering problems.

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