Integrating sqrt(9x^2-1) Using an Integration Table - How-To Guide

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To evaluate the integral of sqrt(9x^2-1) using an integration table, start by factoring out 9 from the expression, transforming it into 3*sqrt(x^2 - 1/9). This allows for easier integration by recognizing it aligns with standard forms in integration tables. A suggested method is to apply a trigonometric substitution, although the discussion notes that this may not be the preferred approach if strictly using the integration table. The key takeaway is to simplify the integral to match known forms for effective evaluation. Understanding these steps is crucial for successfully integrating the function.
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using integration table evaluate the following integral sqrt(9x^2-1)

I just need to know how to start this off, i tried u substitution:

u=9x^2-1 du=18xdx integral:u^(1/2)du/18x. but I don't know how to get rid of the x,

So then from there i tried to use from the integration table integral:udv = uv-(integral vdu)
u=u^1/2 dv=1/18x du=u^(3/2)/(3/2) v=
I didn't know how to go about that
 
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heighme said:
using integration table evaluate the following integral sqrt(9x^2-1)

I just need to know how to start this off, i tried u substitution:

u=9x^2-1 du=18xdx integral:u^(1/2)du/18x. but I don't know how to get rid of the x,

So then from there i tried to use from the integration table integral:udv = uv-(integral vdu)
u=u^1/2 dv=1/18x du=u^(3/2)/(3/2) v=
I didn't know how to go about that

Try a trig substitution.
 
Since you explicitly said "using integration table," a trig substitution is probably not the way to go. I'm assuming your integration table has the following integral in it:
\int \sqrt{x^2 - a^2} dx

Factor 9 out of the two terms in the radical to get 9(x^2 - 1/9).
Bring a factor of 3 out of the radical, and outside the integral.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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