X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb/blobdiff_plain/0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a..fac18421f5b3c215e04a32240e04ac6235d17a0f:/math/ec-bin.c

diff --git a/math/ec-bin.c b/math/ec-bin.c
index d91b0343..c7fe96d4 100644
--- a/math/ec-bin.c
+++ b/math/ec-bin.c
@@ -73,6 +73,7 @@ static ec *ecfind(ec_curve *c, ec *d, mp *x)
       v = F_MUL(f, v, u, y);	    /* %$B = A x^{-2} = x + a + b x^{-2}$% */
       y = F_QUADSOLVE(f, y, v);		/* %$z^2 + z = B$% */
       if (y) y = F_MUL(f, y, y, x);	/* %$y = z x$% */
+      /* Hence %$y^2 + x y = (z^2 + z) x^2 = A$% */
     }
     MP_DROP(u);
     MP_DROP(v);