Can you help me with these two integrals?

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These are three functions that I try to integrate by hand, however, I try many methods and they do not work. Can you help me with that?

The first function is:

$$\int_{0}^{2\pi} \frac{1}{\sqrt{1- C\cos(t)}^3}dt\qquad \text{with } 0 < C <1$$

The second function is:

$$\int_{0}^{2\pi } \frac{\cos(t)}{\sqrt{1- C \cos(t)}}dt \qquad \text{with } 0 < C <1$$

The third function is:

$$\int_{0}^{2\pi } \frac{\cos(t)}{\sqrt{1- C \cos(t)}^3}dt \qquad \text{with } 0 < C <1$$

I have tried finding the answer through Maple, however, I could not understand the answer. Here is the answer for the three functions. The first one is: $$\,{\frac {-4}{\sqrt {C+1} \left( -1+C \right) }{\it EllipticE} \left( {\frac {\sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) }$$

The second one is: $$\,{\frac {-4}{\sqrt {C+1}C} \left( C{\it EllipticE} \left( {\frac { \sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) -{\it EllipticK} \left( { \frac {\sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) +{\it EllipticE} \left( {\frac {\sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) \right) }$$

And the third one is: $$-{\frac {4}{ \left( -3+3\,C \right) {C}^{3}} \left( {\it EllipticK} \left( {\sqrt {2}\sqrt {C}{\frac {1}{\sqrt {C+1}}}} \right) {C}^{3}-{ \it EllipticK} \left( {\sqrt {2}\sqrt {C}{\frac {1}{\sqrt {C+1}}}} \right) {C}^{2}-5\,{\it EllipticE} \left( {\frac {\sqrt {2}\sqrt {C} }{\sqrt {C+1}}} \right) {C}^{2}+8\,{\it EllipticK} \left( {\frac { \sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) C-8\,{\it EllipticK} \left( {\frac {\sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) +8\,{\it EllipticE} \left( {\frac {\sqrt {2}\sqrt {C}}{\sqrt {C+1}}} \right) \right) { \frac {1}{\sqrt {C+1}}}}$$

I am trying to understand how Maple can generate these answers, so any help is wonderful for me. Thank you so much!

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Techniques for evaluation of elliptic integrals were worked out in the 19th century. The book I know about is

Hancock, H., Elliptic integrals., New York: J. Wiley and Sons, 104 S. (1917). ZBL46.1469.01.

Many years ago I got the softcover reprint of this from Dover.

Hancock spends a chapter or two on evaluating integrals in terms of the standard elliptic integrals $E, F, K, \Pi$. I can only assume that Maple uses something like these methods.