Incomplete Elliptic K
From specialfunctionswiki
The incomplete elliptic integral of the first kind is $$K(\phi |k) = K(\phi |m) = \displaystyle\int_0^{\phi} \dfrac{1}{\sqrt{1-k^2\sin^2 \theta}} d\theta.$$
See Also
Elliptic K
Incomplete Elliptic E
