On this we calculate x1 as 2.5 times .2 minus
.2-squared which is equal to .4.
x2 is 2.5 times .4 minus .4-squared.
That's equal to .6. And x3 is equal to 2.5 times
.6 minus .6-squared and that's equal to
.6. Ah! They're the same. This is our fixed point
and b was the correct answer.