find the indefinite integral x^-13 dx
when you are integrating a power series you add 1 to the exponent and divide by that exponent, and make to to add C since its indefinite
\[\bf \int\limits_{}^{}x^ndx=\frac{ x^{n+1} }{ n+1 }\]\[\bf \int\limits_{}^{}x^{-13}dx=? \]
+ C; I forgot the constant.
x^-12/-12+C
Correct.
Awesome!! Thank you!!
$$\begin{align*}\int x^{-13}\,\mathrm{d}x&=-\frac1{12}\int\left(-12x^{-13}\right)\,\mathrm{d}x\\&=-\frac1{12}\int\frac{\mathrm{d}}{\mathrm{d}x}\left(x^{-12}\right)\,\mathrm{d}x\\&=-\frac1{12}x^{-12}+C\end{align*}$$
@oldrin.bataku Don't give away answers.
It's not quite giving away an answer if it was already previously posted, not to mention I accompanied it with work that demonstrate why the rule works.$$\int x^n\,dx=\frac1{n+1}\int((n+1)x^n)\,dx=\frac1{n+1}\int\frac{d}{dx}\left(x^{n+1}\right)\,dx=\frac1{n+1}x^{n+1}+C$$
The rule works because you are inversely differentiating..If:\[\bf f(x)=x^n \ then \ f'(x)=nx^{n-1}\], then inversely differentiating, i.e. adding 1 to the exponent and then dividing by this new exponent brings you to the antiderivative.
This is obviously not an argument, just a complement to what you've already posted.
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