Calculating the Integral of a Rational Function

electronic engineer
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how to calculate the calculus of this rational function:

\int \frac{dx}{{x+x^6}}

could anyone get me through the solution?!
 
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Hint:

\frac{1}{{x + x^6 }} = \frac{1}{{x\left( {1 + x^5 } \right)}} = \frac{{\frac{1}{{x^6 }}}}{{\frac{{1 + x^5 }}{{x^5 }}}} = \frac{{\frac{1}{{x^6 }}}}{{\frac{1}{{x^5 }} + 1}}
 
so final result:

-0.2* ln(1+x^-5)


is that right?
 
Last edited:
electronic engineer said:
so final result:

-0.2* ln(1+x^-5)


is that right?
Indeed, if you don't forget the constant of integration :wink:
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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