To C or not to C - split -Integral

Steven G

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Consider the standard integral of arcsin(u)\arcsin(u), which is
arcsin(u)=11u2du\arcsin(u)=\int \frac{1}{\sqrt{1-u^2}}\,duNotice your problem resembles it (in red).
x3x4dx=x31x43dx=x311x43dx\int\frac{x}{\sqrt{3-x^4}}\,dx=\int\frac{x}{\sqrt{3}\sqrt{1-\frac{x^4}{3}}}\,dx=\int\frac{x}{\sqrt{3}}\cdot \red{\frac{1}{\sqrt{1-\frac{x^4}{3}}}}\,dxIf you recognized that, it's an obvious choice to make a u-subsitution u2=x43u^2=\frac{x^4}{3} or u=x23u=\frac{x^2}{\sqrt{3}}.
I'll let you work out the details but clearly, this isn't something you're expected to do and I second Dr.P's comments. It's more valuable for you.
+C
 
Where do you want put that '+C'

The response in response #11 has the integral sign - the process of integration has not been finished.

But the corner is really dark - so you may not have noticed it.:devilish::p
The 2nd line of the post should have a +C. To the corner SM.
 
arcsin(u) → ∫1/(1−u2)du
This one?? I would agree to put a 'C' if it were written the other way:

∫1/(1−u2)du = arcsin(u) + C

Do we also have to state that 'u' is a real number?

(and thank you for speaking-up for me in another thread.)
 
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