Find the indefinite integral of the given problem

In summary, the conversation was about the steps to solve a problem involving the constant ##\frac{2}{\sqrt 3}##. There was a discussion about multiplying each term by this constant and using a change of variable to simplify the problem. There was also a question about whether there was a missing factor of ##\frac{1}{2}## in the final solution. The conversation ended with agreement that a change of variable was necessary due to the square root sign.
  • #1
chwala
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Homework Statement
see attached
Relevant Equations
##\dfrac{d}{dx} \left[\tan^{-1}x\right]= \dfrac{1}{x^2+1}##
Now the steps to solution are clear to me...My interest is on the constant that was factored out i.e ##\frac{2}{\sqrt 3}##...

1654595333253.png
the steps that were followed are; They multiplied each term by ##\dfrac{2}{\sqrt 3}## to realize,

##\dfrac{2}{\sqrt 3}\int \dfrac{dx}{\left[\dfrac{2}{\sqrt 3}⋅\dfrac{2x+1}{2}\right]^2+\left[\dfrac{2}{\sqrt 3}⋅\dfrac{\sqrt 3}{2}\right]^2} ##

...

Correct? Is there a different approach guys?

Now, bringing me to my question...see problem below;

1654596731100.png


Are they missing ##\dfrac{1}{2}## somewhere?? In this case we are dividing each term by ##2^2##... we ought to have;

... ##\dfrac{1}{2}\sin^{-1} \left[\frac{x+1}{2}\right] + c##

I hope i did not overlook anything...
 
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  • #2
[tex]
\int \frac{1}{\sqrt{2^2 - (x + 1)^2}}\,dx = \int \frac{1}{2\sqrt{1 - u^2}}(2\,du)[/tex] with [itex]u = (x + 1)/2[/itex].
 
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  • #3
pasmith said:
[tex]
\int \frac{1}{\sqrt{2^2 - (x + 1)^2}}\,dx = \int \frac{1}{2\sqrt{1 - u^2}}(2\,du)[/tex] with [itex]u = (x + 1)/2[/itex].
Thanks ...cheers man!
 
  • #4
Aaaargh! because of the square root sign! That calls for 'change of variable' ...was wondering why...great day!
 

FAQ: Find the indefinite integral of the given problem

What is an indefinite integral?

An indefinite integral is a mathematical concept used in calculus to find the antiderivative of a given function. It represents the set of all possible functions whose derivative is equal to the original function.

How do I find the indefinite integral of a given problem?

To find the indefinite integral, you need to use the integral symbol (∫) and the variable of integration. Then, you can use integration techniques such as substitution, integration by parts, or partial fractions to solve the problem.

What is the difference between definite and indefinite integrals?

A definite integral has specific limits of integration, while an indefinite integral does not. This means that a definite integral will give a numerical value, while an indefinite integral will give a general formula for the antiderivative.

Can I use a calculator to find the indefinite integral?

Yes, there are many online calculators and software programs that can help you find the indefinite integral of a given problem. However, it is important to understand the concepts and techniques behind integration in order to use these tools effectively.

Why is finding the indefinite integral important?

Finding the indefinite integral allows us to solve a wide range of problems in mathematics, physics, and engineering. It also helps us understand the behavior and relationships between different functions, and is a fundamental concept in calculus.

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