Gokyo Shumyo, Section 1, Problem 64 / Solution

Main line  

is the only way. After Black has found the vital point, this line is straightforward.

Variation: no ko  

There is no ko at here: reveals shortage of liberties.

Failure 1  

After , a and b are miai.

Failure 2  

White will make a killing shape inside Black's eye space. See nakade or almost fill.