Let $f$ be an analytic function in some sector in the complex plane behaving as $$f(z)=\mathcal O(z^n)$$ for some $n$ as $z\to\infty$. Can one prove in general that line integrals of $f$ (in this sector) behave as $$\int_{z_0}^z f(w)dw=\mathcal O(z^{n+1})$$ ?
I hope the question is posed clearly enough. Thank you all very much in advance!
Regards, Frank
Integrals are monotone, so since $|f(z)|\le M|z^n|$ we have for a reasonable path $\gamma$ from $z_0$ to $z$:
$$\left|\int_\gamma f(z)\right|\le\int_\gamma |f(z)|\le M\int_\gamma |z^n|\le M'|z|^{n+1}$$