Squaring n-bit int vs. multiplying two n-bit ints

Question

Disclaimer: Homework question. I\'m looking for a hint…

Professor F. Lake tells his class that it is asymptotically faster to square an n-bit integer than to multip

Answer 1

Here's a hint.

And here's my solution in SECRET CODE:Fdhnevat zrnaf lbh bayl unir gb qb bar vavgvny SG, abg gjb, fb vg'f snfgre.